The crystal structures of 2-oxo-2-phenyl-
N-[(
R)-1-phenylethyl]acetamide, C
16H
15NO
2, (I), and
N,
N-dimethyl-2-(1-naphthyl)-2-oxoacetamide, C
14H
13NO
2, (II), were determined in an attempt to understand the reason for the lack of Yang photocyclization in their respective crystals. In the case of (I), the long distance between the O atom of the carbonyl group and the
-H atom, and between the C atom of the carbonyl group and the
-C atom, preclude Yang photocyclization. For (II), the deviation of the
-H atom from the plane of the carbonyl group and interactions between the naphthalene rings are regarded as possible reasons for the chemical inertia. The two independent molecules of (I) differ in their conformation. N-H
O hydrogen bonds link molecules of (I) into chains extended along the
b axis.
Supporting information
CCDC references: 746072; 746073
Compound (I) having the R configuration and compound (II) were purchased
from Sigma–Aldrich. [Recrystallisation from which solvent?]
H atoms for (I) were positioned geometrically and treated as riding, with C—H
= 0.93–0.98 Å and Uiso = 1.5Ueq(C) for a methyl group or
1.2Ueq(C) for other groups. The N-bound H atom was located in a
difference Fourier map and refined without constraints. For (II), only the H
atoms on C14 were treated as riding.
For both compounds, data collection: CrysAlis CCD (Oxford Diffraction, 2003); cell refinement: CrysAlis CCD (Oxford Diffraction, 2003); data reduction: CrysAlis RED (Oxford Diffraction, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).
(I) 2-Oxo-2-phenyl-
N-[(
R)-1-phenylethyl]acetamide
top
Crystal data top
C16H15NO2 | Z = 2 |
Mr = 253.29 | F(000) = 268 |
Triclinic, P1 | Dx = 1.243 Mg m−3 |
Hall symbol: P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 8.593 (2) Å | Cell parameters from 1169 reflections |
b = 9.761 (2) Å | θ = 2.7–19.7° |
c = 10.054 (3) Å | µ = 0.08 mm−1 |
α = 93.32 (2)° | T = 299 K |
β = 114.45 (3)° | Block, colourless |
γ = 113.75 (3)° | 0.50 × 0.30 × 0.15 mm |
V = 676.6 (3) Å3 | |
Data collection top
Kuma KM4 CCD diffractometer | 1671 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.043 |
Graphite monochromator | θmax = 25.0°, θmin = 3.1° |
ω scans | h = −10→10 |
3656 measured reflections | k = −9→11 |
2248 independent reflections | l = −11→11 |
Refinement top
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.061 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.170 | w = 1/[σ2(Fo2) + (0.1105P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.05 | (Δ/σ)max < 0.001 |
2248 reflections | Δρmax = 0.36 e Å−3 |
349 parameters | Δρmin = −0.20 e Å−3 |
3 restraints | Absolute structure: The absolute structure was assigned according to the information
from Sigma–Aldrich. |
Primary atom site location: structure-invariant direct methods | |
Crystal data top
C16H15NO2 | γ = 113.75 (3)° |
Mr = 253.29 | V = 676.6 (3) Å3 |
Triclinic, P1 | Z = 2 |
a = 8.593 (2) Å | Mo Kα radiation |
b = 9.761 (2) Å | µ = 0.08 mm−1 |
c = 10.054 (3) Å | T = 299 K |
α = 93.32 (2)° | 0.50 × 0.30 × 0.15 mm |
β = 114.45 (3)° | |
Data collection top
Kuma KM4 CCD diffractometer | 1671 reflections with I > 2σ(I) |
3656 measured reflections | Rint = 0.043 |
2248 independent reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.061 | 3 restraints |
wR(F2) = 0.170 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | Δρmax = 0.36 e Å−3 |
2248 reflections | Δρmin = −0.20 e Å−3 |
349 parameters | Absolute structure: The absolute structure was assigned according to the information
from Sigma–Aldrich. |
Special details top
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes)
are estimated using the full covariance matrix. The cell e.s.d.'s are taken
into account individually in the estimation of e.s.d.'s in distances, angles
and torsion angles; correlations between e.s.d.'s in cell parameters are only
used when they are defined by crystal symmetry. An approximate (isotropic)
treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s.
planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor
wR and goodness of fit S are based on F2, conventional
R-factors R are based on F, with F set to zero for
negative F2. The threshold expression of F2 >
σ(F2) is used only for calculating R-factors(gt) etc.
and is not relevant to the choice of reflections for refinement.
R-factors based on F2 are statistically about twice as large
as those based on F, and R- factors based on ALL data will be
even larger. |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
C1A | 0.8298 (8) | 0.2058 (6) | 0.2069 (6) | 0.0645 (13) | |
H1A | 0.7285 | 0.1553 | 0.1084 | 0.077* | |
C2A | 1.0168 (9) | 0.2522 (7) | 0.2349 (7) | 0.0745 (15) | |
H2A | 1.0420 | 0.2341 | 0.1560 | 0.089* | |
C3A | 1.1649 (9) | 0.3251 (7) | 0.3797 (8) | 0.0825 (17) | |
H3A | 1.2918 | 0.3573 | 0.3994 | 0.099* | |
C4A | 1.1285 (8) | 0.3511 (8) | 0.4957 (8) | 0.0850 (18) | |
H4A | 1.2305 | 0.3985 | 0.5942 | 0.102* | |
C5A | 0.9448 (8) | 0.3086 (7) | 0.4690 (6) | 0.0745 (15) | |
H5A | 0.9219 | 0.3300 | 0.5486 | 0.089* | |
C6A | 0.7901 (7) | 0.2328 (5) | 0.3219 (5) | 0.0537 (11) | |
C7A | 0.5919 (8) | 0.1911 (6) | 0.2926 (6) | 0.0644 (13) | |
C8A | 0.4269 (7) | 0.0721 (6) | 0.1422 (7) | 0.0626 (12) | |
C9A | 0.1641 (7) | 0.0279 (6) | −0.1094 (6) | 0.0637 (13) | |
H9A | 0.1572 | −0.0750 | −0.1229 | 0.076* | |
C10A | −0.0292 (6) | 0.0056 (5) | −0.1274 (6) | 0.0557 (11) | |
C11A | −0.1068 (8) | 0.0993 (6) | −0.1885 (7) | 0.0701 (14) | |
H11A | −0.0375 | 0.1832 | −0.2154 | 0.084* | |
C12A | −0.2912 (10) | 0.0683 (9) | −0.2104 (8) | 0.091 (2) | |
H12A | −0.3458 | 0.1305 | −0.2531 | 0.110* | |
C13A | −0.3893 (9) | −0.0540 (9) | −0.1684 (8) | 0.089 (2) | |
H13A | −0.5116 | −0.0752 | −0.1827 | 0.107* | |
C14A | −0.3115 (11) | −0.1440 (9) | −0.1069 (9) | 0.095 (2) | |
H14A | −0.3793 | −0.2267 | −0.0778 | 0.114* | |
C15A | −0.1334 (9) | −0.1143 (7) | −0.0869 (7) | 0.0786 (15) | |
H15A | −0.0812 | −0.1779 | −0.0443 | 0.094* | |
C16A | 0.2142 (10) | 0.0996 (9) | −0.2256 (8) | 0.0927 (19) | |
H16A | 0.3368 | 0.1089 | −0.2088 | 0.139* | |
H16B | 0.2215 | 0.2007 | −0.2156 | 0.139* | |
H16C | 0.1159 | 0.0345 | −0.3258 | 0.139* | |
N1A | 0.3198 (6) | 0.1215 (5) | 0.0463 (5) | 0.0621 (11) | |
HN1A | 0.345 (8) | 0.227 (7) | 0.076 (6) | 0.074* | |
O1A | 0.5531 (6) | 0.2432 (6) | 0.3800 (5) | 0.0995 (15) | |
O2A | 0.4054 (6) | −0.0616 (4) | 0.1194 (5) | 0.0880 (13) | |
C1B | −0.0127 (8) | 0.5380 (6) | 0.0496 (6) | 0.0611 (12) | |
H1B | 0.0883 | 0.5585 | 0.1452 | 0.073* | |
C2B | −0.1918 (9) | 0.5111 (7) | 0.0328 (8) | 0.0761 (16) | |
H2B | −0.2110 | 0.5146 | 0.1172 | 0.091* | |
C3B | −0.3401 (8) | 0.4795 (7) | −0.1084 (9) | 0.0837 (18) | |
H3B | −0.4602 | 0.4623 | −0.1200 | 0.100* | |
C4B | −0.3131 (9) | 0.4732 (9) | −0.2303 (8) | 0.100 (2) | |
H4B | −0.4161 | 0.4481 | −0.3262 | 0.120* | |
C5B | −0.1350 (8) | 0.5033 (8) | −0.2154 (7) | 0.0814 (17) | |
H5B | −0.1175 | 0.5024 | −0.3006 | 0.098* | |
C6B | 0.0160 (6) | 0.5343 (5) | −0.0763 (5) | 0.0529 (11) | |
C7B | 0.2036 (7) | 0.5603 (5) | −0.0624 (5) | 0.0573 (12) | |
C8B | 0.3506 (7) | 0.5522 (5) | 0.0814 (6) | 0.0544 (11) | |
C9B | 0.6092 (7) | 0.6812 (6) | 0.3414 (6) | 0.0599 (12) | |
H9B | 0.5664 | 0.5741 | 0.3497 | 0.072* | |
C10B | 0.8102 (7) | 0.7420 (5) | 0.3616 (5) | 0.0534 (11) | |
C11B | 0.8882 (8) | 0.8619 (6) | 0.3067 (7) | 0.0733 (15) | |
H11B | 0.8122 | 0.9040 | 0.2486 | 0.088* | |
C12B | 1.0776 (9) | 0.9209 (7) | 0.3363 (8) | 0.0857 (18) | |
H12B | 1.1290 | 1.0043 | 0.3004 | 0.103* | |
C13B | 1.1892 (9) | 0.8598 (8) | 0.4163 (9) | 0.0877 (18) | |
H13B | 1.3166 | 0.8998 | 0.4346 | 0.105* | |
C14B | 1.1143 (9) | 0.7380 (9) | 0.4709 (8) | 0.091 (2) | |
H14B | 1.1907 | 0.6952 | 0.5269 | 0.110* | |
C15B | 0.9268 (9) | 0.6801 (7) | 0.4424 (7) | 0.0784 (16) | |
H15B | 0.8763 | 0.5966 | 0.4786 | 0.094* | |
C16B | 0.6068 (9) | 0.7743 (10) | 0.4662 (7) | 0.096 (2) | |
H16D | 0.4769 | 0.7328 | 0.4513 | 0.144* | |
H16E | 0.6529 | 0.8810 | 0.4634 | 0.144* | |
H16F | 0.6891 | 0.7682 | 0.5630 | 0.144* | |
N1B | 0.4691 (6) | 0.6779 (4) | 0.1952 (5) | 0.0584 (10) | |
HN1B | 0.447 (8) | 0.766 (7) | 0.172 (6) | 0.070* | |
O1B | 0.2394 (6) | 0.5755 (7) | −0.1671 (5) | 0.1039 (16) | |
O2B | 0.3527 (6) | 0.4268 (4) | 0.0846 (5) | 0.0849 (12) | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
C1A | 0.065 (3) | 0.069 (3) | 0.053 (3) | 0.031 (2) | 0.023 (3) | 0.012 (2) |
C2A | 0.078 (4) | 0.079 (3) | 0.076 (4) | 0.040 (3) | 0.041 (3) | 0.024 (3) |
C3A | 0.061 (4) | 0.082 (4) | 0.101 (5) | 0.033 (3) | 0.035 (4) | 0.027 (3) |
C4A | 0.058 (4) | 0.102 (5) | 0.068 (4) | 0.040 (3) | 0.008 (3) | 0.005 (3) |
C5A | 0.076 (4) | 0.092 (4) | 0.054 (3) | 0.050 (3) | 0.021 (3) | 0.012 (3) |
C6A | 0.056 (3) | 0.054 (2) | 0.052 (3) | 0.033 (2) | 0.019 (2) | 0.014 (2) |
C7A | 0.069 (3) | 0.069 (3) | 0.062 (3) | 0.040 (3) | 0.028 (3) | 0.019 (2) |
C8A | 0.062 (3) | 0.056 (3) | 0.085 (4) | 0.037 (2) | 0.038 (3) | 0.029 (2) |
C9A | 0.058 (3) | 0.054 (2) | 0.069 (3) | 0.028 (2) | 0.021 (3) | 0.004 (2) |
C10A | 0.050 (3) | 0.055 (3) | 0.055 (3) | 0.025 (2) | 0.020 (2) | 0.009 (2) |
C11A | 0.073 (3) | 0.060 (3) | 0.082 (4) | 0.038 (3) | 0.034 (3) | 0.020 (3) |
C12A | 0.080 (4) | 0.109 (5) | 0.085 (4) | 0.064 (4) | 0.023 (4) | 0.008 (4) |
C13A | 0.057 (3) | 0.099 (5) | 0.095 (5) | 0.028 (3) | 0.033 (4) | −0.004 (4) |
C14A | 0.089 (5) | 0.088 (4) | 0.108 (5) | 0.031 (4) | 0.057 (4) | 0.026 (4) |
C15A | 0.075 (4) | 0.069 (3) | 0.087 (4) | 0.031 (3) | 0.037 (3) | 0.024 (3) |
C16A | 0.073 (4) | 0.115 (5) | 0.083 (4) | 0.036 (4) | 0.041 (4) | 0.013 (4) |
N1A | 0.056 (2) | 0.045 (2) | 0.075 (3) | 0.0262 (18) | 0.021 (2) | 0.0081 (19) |
O1A | 0.085 (3) | 0.143 (4) | 0.081 (3) | 0.065 (3) | 0.040 (2) | 0.006 (3) |
O2A | 0.088 (3) | 0.059 (2) | 0.108 (3) | 0.041 (2) | 0.033 (2) | 0.023 (2) |
C1B | 0.062 (3) | 0.071 (3) | 0.058 (3) | 0.035 (2) | 0.031 (3) | 0.020 (2) |
C2B | 0.078 (4) | 0.082 (4) | 0.099 (5) | 0.044 (3) | 0.060 (4) | 0.033 (3) |
C3B | 0.051 (3) | 0.082 (4) | 0.111 (5) | 0.029 (3) | 0.036 (4) | 0.013 (3) |
C4B | 0.056 (4) | 0.137 (6) | 0.074 (4) | 0.051 (4) | 0.002 (3) | −0.004 (4) |
C5B | 0.067 (4) | 0.115 (5) | 0.053 (3) | 0.044 (3) | 0.021 (3) | 0.010 (3) |
C6B | 0.048 (2) | 0.053 (2) | 0.054 (3) | 0.024 (2) | 0.021 (2) | 0.010 (2) |
C7B | 0.051 (3) | 0.063 (3) | 0.052 (3) | 0.023 (2) | 0.025 (2) | 0.005 (2) |
C8B | 0.048 (3) | 0.052 (3) | 0.063 (3) | 0.024 (2) | 0.027 (2) | 0.009 (2) |
C9B | 0.059 (3) | 0.065 (3) | 0.056 (3) | 0.034 (2) | 0.022 (2) | 0.017 (2) |
C10B | 0.057 (3) | 0.058 (3) | 0.051 (3) | 0.036 (2) | 0.022 (2) | 0.013 (2) |
C11B | 0.071 (3) | 0.075 (3) | 0.088 (4) | 0.045 (3) | 0.038 (3) | 0.037 (3) |
C12B | 0.078 (4) | 0.085 (4) | 0.109 (5) | 0.041 (3) | 0.053 (4) | 0.041 (4) |
C13B | 0.066 (4) | 0.100 (4) | 0.102 (5) | 0.044 (3) | 0.039 (4) | 0.021 (4) |
C14B | 0.071 (4) | 0.116 (5) | 0.100 (5) | 0.062 (4) | 0.032 (4) | 0.043 (4) |
C15B | 0.075 (4) | 0.083 (4) | 0.093 (4) | 0.049 (3) | 0.040 (3) | 0.042 (3) |
C16B | 0.070 (4) | 0.144 (6) | 0.067 (4) | 0.054 (4) | 0.027 (3) | 0.007 (4) |
N1B | 0.056 (2) | 0.049 (2) | 0.061 (2) | 0.0297 (18) | 0.016 (2) | 0.0092 (18) |
O1B | 0.077 (3) | 0.164 (5) | 0.068 (3) | 0.047 (3) | 0.042 (2) | 0.025 (3) |
O2B | 0.091 (3) | 0.0501 (19) | 0.099 (3) | 0.0392 (18) | 0.029 (2) | 0.0066 (18) |
Geometric parameters (Å, º) top
C1A—C6A | 1.373 (7) | C1B—C2B | 1.386 (7) |
C1A—C2A | 1.375 (7) | C1B—C6B | 1.387 (7) |
C1A—H1A | 0.9300 | C1B—H1B | 0.9300 |
C2A—C3A | 1.365 (9) | C2B—C3B | 1.368 (10) |
C2A—H2A | 0.9300 | C2B—H2B | 0.9300 |
C3A—C4A | 1.361 (9) | C3B—C4B | 1.340 (10) |
C3A—H3A | 0.9300 | C3B—H3B | 0.9300 |
C4A—C5A | 1.358 (8) | C4B—C5B | 1.376 (9) |
C4A—H4A | 0.9300 | C4B—H4B | 0.9300 |
C5A—C6A | 1.398 (7) | C5B—C6B | 1.365 (7) |
C5A—H5A | 0.9300 | C5B—H5B | 0.9300 |
C6A—C7A | 1.472 (7) | C6B—C7B | 1.471 (6) |
C7A—O1A | 1.212 (7) | C7B—O1B | 1.215 (6) |
C7A—C8A | 1.530 (8) | C7B—C8B | 1.507 (7) |
C8A—O2A | 1.236 (6) | C8B—O2B | 1.234 (6) |
C8A—N1A | 1.298 (7) | C8B—N1B | 1.311 (6) |
C9A—N1A | 1.480 (7) | C9B—N1B | 1.452 (6) |
C9A—C10A | 1.515 (7) | C9B—C10B | 1.500 (7) |
C9A—C16A | 1.519 (9) | C9B—C16B | 1.518 (8) |
C9A—H9A | 0.9800 | C9B—H9B | 0.9800 |
C10A—C15A | 1.361 (7) | C10B—C11B | 1.368 (7) |
C10A—C11A | 1.370 (7) | C10B—C15B | 1.378 (7) |
C11A—C12A | 1.403 (8) | C11B—C12B | 1.376 (8) |
C11A—H11A | 0.9300 | C11B—H11B | 0.9300 |
C12A—C13A | 1.362 (10) | C12B—C13B | 1.342 (9) |
C12A—H12A | 0.9300 | C12B—H12B | 0.9300 |
C13A—C14A | 1.340 (10) | C13B—C14B | 1.371 (10) |
C13A—H13A | 0.9300 | C13B—H13B | 0.9300 |
C14A—C15A | 1.360 (8) | C14B—C15B | 1.365 (8) |
C14A—H14A | 0.9300 | C14B—H14B | 0.9300 |
C15A—H15A | 0.9300 | C15B—H15B | 0.9300 |
C16A—H16A | 0.9600 | C16B—H16D | 0.9600 |
C16A—H16B | 0.9600 | C16B—H16E | 0.9600 |
C16A—H16C | 0.9600 | C16B—H16F | 0.9600 |
N1A—HN1A | 0.97 (6) | N1B—HN1B | 0.98 (6) |
| | | |
C6A—C1A—C2A | 121.1 (5) | C2B—C1B—C6B | 120.0 (5) |
C6A—C1A—H1A | 119.5 | C2B—C1B—H1B | 120.0 |
C2A—C1A—H1A | 119.5 | C6B—C1B—H1B | 120.0 |
C3A—C2A—C1A | 119.3 (6) | C3B—C2B—C1B | 119.6 (6) |
C3A—C2A—H2A | 120.4 | C3B—C2B—H2B | 120.2 |
C1A—C2A—H2A | 120.4 | C1B—C2B—H2B | 120.2 |
C4A—C3A—C2A | 120.5 (6) | C4B—C3B—C2B | 120.2 (6) |
C4A—C3A—H3A | 119.7 | C4B—C3B—H3B | 119.9 |
C2A—C3A—H3A | 119.7 | C2B—C3B—H3B | 119.9 |
C5A—C4A—C3A | 120.7 (6) | C3B—C4B—C5B | 120.9 (6) |
C5A—C4A—H4A | 119.6 | C3B—C4B—H4B | 119.5 |
C3A—C4A—H4A | 119.6 | C5B—C4B—H4B | 119.5 |
C4A—C5A—C6A | 119.9 (6) | C6B—C5B—C4B | 120.4 (6) |
C4A—C5A—H5A | 120.0 | C6B—C5B—H5B | 119.8 |
C6A—C5A—H5A | 120.0 | C4B—C5B—H5B | 119.8 |
C1A—C6A—C5A | 118.4 (5) | C5B—C6B—C1B | 118.7 (5) |
C1A—C6A—C7A | 121.7 (4) | C5B—C6B—C7B | 120.0 (4) |
C5A—C6A—C7A | 119.8 (5) | C1B—C6B—C7B | 121.2 (4) |
O1A—C7A—C6A | 124.3 (5) | O1B—C7B—C6B | 122.4 (5) |
O1A—C7A—C8A | 119.1 (5) | O1B—C7B—C8B | 118.1 (5) |
C6A—C7A—C8A | 116.6 (4) | C6B—C7B—C8B | 119.2 (4) |
O2A—C8A—N1A | 124.7 (5) | O2B—C8B—N1B | 123.6 (5) |
O2A—C8A—C7A | 118.9 (5) | O2B—C8B—C7B | 117.7 (4) |
N1A—C8A—C7A | 116.4 (4) | N1B—C8B—C7B | 118.7 (4) |
N1A—C9A—C10A | 110.1 (4) | N1B—C9B—C10B | 113.9 (4) |
N1A—C9A—C16A | 110.4 (4) | N1B—C9B—C16B | 109.0 (4) |
C10A—C9A—C16A | 113.8 (5) | C10B—C9B—C16B | 111.1 (4) |
N1A—C9A—H9A | 107.4 | N1B—C9B—H9B | 107.5 |
C10A—C9A—H9A | 107.4 | C10B—C9B—H9B | 107.5 |
C16A—C9A—H9A | 107.4 | C16B—C9B—H9B | 107.5 |
C15A—C10A—C11A | 118.4 (5) | C11B—C10B—C15B | 117.3 (5) |
C15A—C10A—C9A | 119.4 (5) | C11B—C10B—C9B | 122.7 (4) |
C11A—C10A—C9A | 122.1 (4) | C15B—C10B—C9B | 119.9 (5) |
C10A—C11A—C12A | 119.8 (5) | C10B—C11B—C12B | 120.8 (5) |
C10A—C11A—H11A | 120.1 | C10B—C11B—H11B | 119.6 |
C12A—C11A—H11A | 120.1 | C12B—C11B—H11B | 119.6 |
C13A—C12A—C11A | 119.2 (6) | C13B—C12B—C11B | 120.9 (6) |
C13A—C12A—H12A | 120.4 | C13B—C12B—H12B | 119.5 |
C11A—C12A—H12A | 120.4 | C11B—C12B—H12B | 119.5 |
C14A—C13A—C12A | 120.8 (6) | C12B—C13B—C14B | 119.6 (6) |
C14A—C13A—H13A | 119.6 | C12B—C13B—H13B | 120.2 |
C12A—C13A—H13A | 119.6 | C14B—C13B—H13B | 120.2 |
C13A—C14A—C15A | 119.9 (6) | C15B—C14B—C13B | 119.5 (5) |
C13A—C14A—H14A | 120.0 | C15B—C14B—H14B | 120.3 |
C15A—C14A—H14A | 120.0 | C13B—C14B—H14B | 120.3 |
C14A—C15A—C10A | 121.9 (6) | C14B—C15B—C10B | 121.8 (5) |
C14A—C15A—H15A | 119.0 | C14B—C15B—H15B | 119.1 |
C10A—C15A—H15A | 119.0 | C10B—C15B—H15B | 119.1 |
C9A—C16A—H16A | 109.5 | C9B—C16B—H16D | 109.5 |
C9A—C16A—H16B | 109.5 | C9B—C16B—H16E | 109.5 |
H16A—C16A—H16B | 109.5 | H16D—C16B—H16E | 109.5 |
C9A—C16A—H16C | 109.5 | C9B—C16B—H16F | 109.5 |
H16A—C16A—H16C | 109.5 | H16D—C16B—H16F | 109.5 |
H16B—C16A—H16C | 109.5 | H16E—C16B—H16F | 109.5 |
C8A—N1A—C9A | 124.3 (4) | C8B—N1B—C9B | 123.3 (4) |
C8A—N1A—HN1A | 119 (3) | C8B—N1B—HN1B | 112 (3) |
C9A—N1A—HN1A | 117 (3) | C9B—N1B—HN1B | 124 (3) |
| | | |
C6A—C1A—C2A—C3A | 0.5 (8) | C6B—C1B—C2B—C3B | 0.6 (8) |
C1A—C2A—C3A—C4A | 0.4 (9) | C1B—C2B—C3B—C4B | 0.6 (10) |
C2A—C3A—C4A—C5A | −1.7 (10) | C2B—C3B—C4B—C5B | −2.2 (11) |
C3A—C4A—C5A—C6A | 2.1 (9) | C3B—C4B—C5B—C6B | 2.6 (11) |
C2A—C1A—C6A—C5A | −0.1 (7) | C4B—C5B—C6B—C1B | −1.3 (9) |
C2A—C1A—C6A—C7A | 176.8 (5) | C4B—C5B—C6B—C7B | 177.6 (6) |
C4A—C5A—C6A—C1A | −1.2 (8) | C2B—C1B—C6B—C5B | −0.3 (7) |
C4A—C5A—C6A—C7A | −178.2 (5) | C2B—C1B—C6B—C7B | −179.1 (5) |
C1A—C6A—C7A—O1A | −161.9 (6) | C5B—C6B—C7B—O1B | 9.9 (8) |
C5A—C6A—C7A—O1A | 15.0 (8) | C1B—C6B—C7B—O1B | −171.2 (6) |
C1A—C6A—C7A—C8A | 19.1 (6) | C5B—C6B—C7B—C8B | −164.0 (5) |
C5A—C6A—C7A—C8A | −164.0 (5) | C1B—C6B—C7B—C8B | 14.9 (6) |
O1A—C7A—C8A—O2A | −114.8 (6) | O1B—C7B—C8B—O2B | −80.3 (7) |
C6A—C7A—C8A—O2A | 64.3 (6) | C6B—C7B—C8B—O2B | 93.8 (6) |
O1A—C7A—C8A—N1A | 65.9 (7) | O1B—C7B—C8B—N1B | 99.3 (6) |
C6A—C7A—C8A—N1A | −115.1 (5) | C6B—C7B—C8B—N1B | −86.6 (5) |
N1A—C9A—C10A—C15A | −86.2 (6) | N1B—C9B—C10B—C11B | 37.6 (7) |
C16A—C9A—C10A—C15A | 149.3 (5) | C16B—C9B—C10B—C11B | −85.9 (7) |
N1A—C9A—C10A—C11A | 96.2 (6) | N1B—C9B—C10B—C15B | −144.5 (5) |
C16A—C9A—C10A—C11A | −28.3 (7) | C16B—C9B—C10B—C15B | 92.0 (6) |
C15A—C10A—C11A—C12A | −1.2 (8) | C15B—C10B—C11B—C12B | −2.2 (8) |
C9A—C10A—C11A—C12A | 176.5 (5) | C9B—C10B—C11B—C12B | 175.7 (5) |
C10A—C11A—C12A—C13A | 0.9 (9) | C10B—C11B—C12B—C13B | 1.8 (10) |
C11A—C12A—C13A—C14A | 0.0 (10) | C11B—C12B—C13B—C14B | −0.8 (11) |
C12A—C13A—C14A—C15A | −0.5 (11) | C12B—C13B—C14B—C15B | 0.3 (11) |
C13A—C14A—C15A—C10A | 0.2 (10) | C13B—C14B—C15B—C10B | −0.9 (11) |
C11A—C10A—C15A—C14A | 0.7 (9) | C11B—C10B—C15B—C14B | 1.8 (9) |
C9A—C10A—C15A—C14A | −177.0 (6) | C9B—C10B—C15B—C14B | −176.2 (6) |
O2A—C8A—N1A—C9A | −4.5 (8) | O2B—C8B—N1B—C9B | −3.7 (8) |
C7A—C8A—N1A—C9A | 174.8 (4) | C7B—C8B—N1B—C9B | 176.7 (4) |
C10A—C9A—N1A—C8A | 118.2 (5) | C10B—C9B—N1B—C8B | 98.7 (5) |
C16A—C9A—N1A—C8A | −115.4 (6) | C16B—C9B—N1B—C8B | −136.7 (5) |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N1A—HN1A···O2B | 0.97 (6) | 1.92 (6) | 2.864 (5) | 166 (5) |
N1B—HN1B···O2Ai | 0.98 (6) | 1.91 (6) | 2.889 (5) | 178 (5) |
Symmetry code: (i) x, y+1, z. |
(II)
N,
N-dimethyl-2-(1-naphthyl)-2-oxoacetamide
top
Crystal data top
C14H13NO2 | F(000) = 960 |
Mr = 227.25 | Dx = 1.283 Mg m−3 |
Orthorhombic, Pbca | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ac 2ab | Cell parameters from 936 reflections |
a = 8.981 (3) Å | θ = 2.6–18.3° |
b = 24.056 (8) Å | µ = 0.09 mm−1 |
c = 10.895 (3) Å | T = 299 K |
V = 2353.8 (13) Å3 | Block, colourless |
Z = 8 | 0.50 × 0.20 × 0.05 mm |
Data collection top
Kuma KM4 CCD diffractometer | 1229 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.051 |
Graphite monochromator | θmax = 25.0°, θmin = 3.4° |
ω scans | h = −10→9 |
11922 measured reflections | k = −28→28 |
2058 independent reflections | l = −9→12 |
Refinement top
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.063 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.158 | w = 1/[σ2(Fo2) + (0.0663P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.11 | (Δ/σ)max < 0.001 |
2058 reflections | Δρmax = 0.11 e Å−3 |
196 parameters | Δρmin = −0.15 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0052 (13) |
Crystal data top
C14H13NO2 | V = 2353.8 (13) Å3 |
Mr = 227.25 | Z = 8 |
Orthorhombic, Pbca | Mo Kα radiation |
a = 8.981 (3) Å | µ = 0.09 mm−1 |
b = 24.056 (8) Å | T = 299 K |
c = 10.895 (3) Å | 0.50 × 0.20 × 0.05 mm |
Data collection top
Kuma KM4 CCD diffractometer | 1229 reflections with I > 2σ(I) |
11922 measured reflections | Rint = 0.051 |
2058 independent reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.063 | 0 restraints |
wR(F2) = 0.158 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.11 | Δρmax = 0.11 e Å−3 |
2058 reflections | Δρmin = −0.15 e Å−3 |
196 parameters | |
Special details top
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes)
are estimated using the full covariance matrix. The cell e.s.d.'s are taken
into account individually in the estimation of e.s.d.'s in distances, angles
and torsion angles; correlations between e.s.d.'s in cell parameters are only
used when they are defined by crystal symmetry. An approximate (isotropic)
treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s.
planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor
wR and goodness of fit S are based on F2, conventional
R-factors R are based on F, with F set to zero for
negative F2. The threshold expression of F2 >
σ(F2) is used only for calculating R-factors(gt) etc.
and is not relevant to the choice of reflections for refinement.
R-factors based on F2 are statistically about twice as large
as those based on F, and R- factors based on ALL data will be
even larger. |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
C1 | 0.1743 (3) | 0.39550 (12) | 0.4483 (2) | 0.0546 (7) | |
C2 | 0.0678 (3) | 0.36805 (15) | 0.3810 (3) | 0.0656 (8) | |
H2 | 0.062 (3) | 0.3255 (11) | 0.392 (2) | 0.066 (8)* | |
C3 | −0.0270 (4) | 0.39654 (16) | 0.3015 (3) | 0.0749 (9) | |
H3 | −0.099 (3) | 0.3766 (11) | 0.258 (3) | 0.089 (10)* | |
C4 | −0.0158 (3) | 0.45193 (16) | 0.2900 (3) | 0.0711 (9) | |
H4 | −0.078 (3) | 0.4738 (12) | 0.230 (3) | 0.097 (10)* | |
C5 | 0.0905 (3) | 0.48238 (12) | 0.3564 (2) | 0.0588 (7) | |
C6 | 0.1031 (4) | 0.54031 (15) | 0.3419 (3) | 0.0726 (9) | |
H6 | 0.033 (3) | 0.5577 (11) | 0.285 (3) | 0.091 (10)* | |
C7 | 0.2047 (4) | 0.56962 (16) | 0.4045 (3) | 0.0795 (10) | |
H7 | 0.209 (3) | 0.6100 (13) | 0.394 (2) | 0.088 (10)* | |
C8 | 0.2990 (4) | 0.54249 (14) | 0.4870 (3) | 0.0758 (9) | |
H8 | 0.375 (3) | 0.5638 (12) | 0.530 (3) | 0.088 (10)* | |
C9 | 0.2910 (3) | 0.48672 (13) | 0.5042 (3) | 0.0631 (8) | |
H9 | 0.362 (3) | 0.4677 (11) | 0.559 (2) | 0.081 (9)* | |
C10 | 0.1883 (3) | 0.45430 (11) | 0.4387 (2) | 0.0523 (7) | |
C11 | 0.2690 (3) | 0.36091 (12) | 0.5270 (2) | 0.0659 (8) | |
C12 | 0.2552 (3) | 0.29838 (12) | 0.5177 (3) | 0.0670 (8) | |
C13 | 0.1006 (6) | 0.2988 (2) | 0.7022 (4) | 0.0929 (12) | |
H13A | 0.102 (4) | 0.3429 (17) | 0.686 (3) | 0.143 (15)* | |
H13B | 0.148 (5) | 0.2937 (15) | 0.773 (4) | 0.138 (17)* | |
H13C | −0.001 (6) | 0.2831 (18) | 0.708 (4) | 0.17 (2)* | |
C14 | 0.1840 (4) | 0.21094 (13) | 0.6054 (3) | 0.1028 (12) | |
H14A | 0.2474 | 0.1976 | 0.5409 | 0.154* | |
H14B | 0.0844 | 0.1976 | 0.5923 | 0.154* | |
H14C | 0.2200 | 0.1976 | 0.6830 | 0.154* | |
N1 | 0.1840 (3) | 0.27131 (10) | 0.6054 (2) | 0.0709 (7) | |
O1 | 0.3681 (3) | 0.37800 (9) | 0.5937 (2) | 0.1033 (9) | |
O2 | 0.3189 (3) | 0.27624 (9) | 0.4311 (2) | 0.0994 (8) | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
C1 | 0.0487 (16) | 0.067 (2) | 0.0480 (15) | −0.0017 (14) | 0.0021 (12) | −0.0017 (13) |
C2 | 0.0601 (19) | 0.073 (2) | 0.0638 (18) | −0.0031 (17) | 0.0021 (14) | −0.0008 (16) |
C3 | 0.064 (2) | 0.095 (3) | 0.066 (2) | −0.0132 (19) | −0.0147 (16) | −0.0012 (18) |
C4 | 0.066 (2) | 0.091 (3) | 0.0562 (18) | 0.0007 (18) | −0.0059 (15) | 0.0105 (17) |
C5 | 0.0568 (18) | 0.074 (2) | 0.0457 (15) | 0.0037 (15) | 0.0086 (13) | 0.0045 (14) |
C6 | 0.081 (2) | 0.076 (2) | 0.0606 (19) | 0.0098 (19) | 0.0094 (17) | 0.0106 (17) |
C7 | 0.096 (3) | 0.065 (2) | 0.077 (2) | −0.002 (2) | 0.019 (2) | 0.0048 (19) |
C8 | 0.078 (2) | 0.072 (3) | 0.078 (2) | −0.0110 (19) | 0.0006 (18) | −0.0056 (18) |
C9 | 0.0639 (19) | 0.064 (2) | 0.0617 (18) | −0.0037 (16) | −0.0017 (15) | −0.0031 (15) |
C10 | 0.0476 (15) | 0.0637 (18) | 0.0456 (14) | −0.0013 (13) | 0.0080 (12) | −0.0002 (13) |
C11 | 0.0668 (19) | 0.067 (2) | 0.0633 (17) | −0.0026 (15) | −0.0064 (15) | −0.0043 (15) |
C12 | 0.0640 (19) | 0.065 (2) | 0.0720 (19) | 0.0070 (15) | −0.0029 (16) | −0.0057 (16) |
C13 | 0.103 (3) | 0.105 (4) | 0.071 (2) | 0.007 (3) | 0.011 (2) | −0.001 (2) |
C14 | 0.112 (3) | 0.066 (2) | 0.131 (3) | 0.006 (2) | −0.008 (2) | 0.018 (2) |
N1 | 0.0752 (18) | 0.0575 (17) | 0.0801 (17) | 0.0079 (12) | −0.0015 (14) | 0.0090 (13) |
O1 | 0.1117 (19) | 0.0809 (16) | 0.1173 (18) | −0.0056 (14) | −0.0566 (15) | 0.0065 (13) |
O2 | 0.0990 (18) | 0.0953 (17) | 0.1038 (17) | 0.0091 (13) | 0.0248 (14) | −0.0238 (14) |
Geometric parameters (Å, º) top
C1—C2 | 1.375 (4) | C8—H8 | 0.97 (3) |
C1—C10 | 1.424 (4) | C9—C10 | 1.403 (4) |
C1—C11 | 1.467 (4) | C9—H9 | 0.98 (3) |
C2—C3 | 1.394 (4) | C11—O1 | 1.220 (3) |
C2—H2 | 1.03 (3) | C11—C12 | 1.513 (4) |
C3—C4 | 1.342 (4) | C12—O2 | 1.225 (3) |
C3—H3 | 0.94 (3) | C12—N1 | 1.321 (3) |
C4—C5 | 1.404 (4) | C13—N1 | 1.453 (4) |
C4—H4 | 1.00 (3) | C13—H13A | 1.07 (4) |
C5—C6 | 1.407 (4) | C13—H13B | 0.89 (4) |
C5—C10 | 1.425 (3) | C13—H13C | 0.99 (5) |
C6—C7 | 1.340 (4) | C14—N1 | 1.452 (4) |
C6—H6 | 0.97 (3) | C14—H14A | 0.9600 |
C7—C8 | 1.397 (5) | C14—H14B | 0.9600 |
C7—H7 | 0.98 (3) | C14—H14C | 0.9600 |
C8—C9 | 1.356 (4) | | |
| | | |
C2—C1—C10 | 119.9 (3) | C10—C9—H9 | 118.3 (16) |
C2—C1—C11 | 116.3 (3) | C9—C10—C1 | 124.9 (3) |
C10—C1—C11 | 123.7 (3) | C9—C10—C5 | 117.5 (3) |
C1—C2—C3 | 121.3 (3) | C1—C10—C5 | 117.6 (3) |
C1—C2—H2 | 116.7 (14) | O1—C11—C1 | 125.4 (3) |
C3—C2—H2 | 122.0 (14) | O1—C11—C12 | 115.8 (3) |
C4—C3—C2 | 120.0 (3) | C1—C11—C12 | 118.5 (3) |
C4—C3—H3 | 120.9 (17) | O2—C12—N1 | 124.7 (3) |
C2—C3—H3 | 119.1 (17) | O2—C12—C11 | 116.5 (3) |
C3—C4—C5 | 121.4 (3) | N1—C12—C11 | 118.8 (3) |
C3—C4—H4 | 122.7 (17) | N1—C13—H13A | 109 (2) |
C5—C4—H4 | 115.8 (17) | N1—C13—H13B | 109 (3) |
C4—C5—C6 | 120.9 (3) | H13A—C13—H13B | 106 (3) |
C4—C5—C10 | 119.7 (3) | N1—C13—H13C | 110 (3) |
C6—C5—C10 | 119.4 (3) | H13A—C13—H13C | 114 (4) |
C7—C6—C5 | 121.2 (3) | H13B—C13—H13C | 109 (4) |
C7—C6—H6 | 122.3 (17) | N1—C14—H14A | 109.5 |
C5—C6—H6 | 116.5 (17) | N1—C14—H14B | 109.5 |
C6—C7—C8 | 119.7 (4) | H14A—C14—H14B | 109.5 |
C6—C7—H7 | 119.2 (17) | N1—C14—H14C | 109.5 |
C8—C7—H7 | 121.1 (17) | H14A—C14—H14C | 109.5 |
C9—C8—C7 | 121.2 (4) | H14B—C14—H14C | 109.5 |
C9—C8—H8 | 119.5 (17) | C12—N1—C14 | 119.5 (3) |
C7—C8—H8 | 119.2 (17) | C12—N1—C13 | 123.4 (3) |
C8—C9—C10 | 121.0 (3) | C14—N1—C13 | 117.1 (3) |
C8—C9—H9 | 120.6 (16) | | |
| | | |
C10—C1—C2—C3 | 0.8 (4) | C4—C5—C10—C9 | −179.1 (2) |
C11—C1—C2—C3 | −178.9 (3) | C6—C5—C10—C9 | 1.6 (3) |
C1—C2—C3—C4 | −0.4 (5) | C4—C5—C10—C1 | 0.9 (3) |
C2—C3—C4—C5 | 0.3 (5) | C6—C5—C10—C1 | −178.4 (2) |
C3—C4—C5—C6 | 178.7 (3) | C2—C1—C11—O1 | −179.4 (3) |
C3—C4—C5—C10 | −0.6 (4) | C10—C1—C11—O1 | 0.9 (4) |
C4—C5—C6—C7 | −179.7 (3) | C2—C1—C11—C12 | 6.9 (4) |
C10—C5—C6—C7 | −0.4 (4) | C10—C1—C11—C12 | −172.8 (2) |
C5—C6—C7—C8 | −0.8 (5) | O1—C11—C12—O2 | −95.0 (3) |
C6—C7—C8—C9 | 0.8 (5) | C1—C11—C12—O2 | 79.4 (3) |
C7—C8—C9—C10 | 0.5 (5) | O1—C11—C12—N1 | 81.2 (4) |
C8—C9—C10—C1 | 178.4 (3) | C1—C11—C12—N1 | −104.4 (3) |
C8—C9—C10—C5 | −1.7 (4) | O2—C12—N1—C14 | 2.8 (4) |
C2—C1—C10—C9 | 179.0 (2) | C11—C12—N1—C14 | −173.1 (3) |
C11—C1—C10—C9 | −1.3 (4) | O2—C12—N1—C13 | −175.5 (3) |
C2—C1—C10—C5 | −1.0 (4) | C11—C12—N1—C13 | 8.6 (5) |
C11—C1—C10—C5 | 178.7 (2) | | |
Experimental details
| (I) | (II) |
Crystal data |
Chemical formula | C16H15NO2 | C14H13NO2 |
Mr | 253.29 | 227.25 |
Crystal system, space group | Triclinic, P1 | Orthorhombic, Pbca |
Temperature (K) | 299 | 299 |
a, b, c (Å) | 8.593 (2), 9.761 (2), 10.054 (3) | 8.981 (3), 24.056 (8), 10.895 (3) |
α, β, γ (°) | 93.32 (2), 114.45 (3), 113.75 (3) | 90, 90, 90 |
V (Å3) | 676.6 (3) | 2353.8 (13) |
Z | 2 | 8 |
Radiation type | Mo Kα | Mo Kα |
µ (mm−1) | 0.08 | 0.09 |
Crystal size (mm) | 0.50 × 0.30 × 0.15 | 0.50 × 0.20 × 0.05 |
|
Data collection |
Diffractometer | Kuma KM4 CCD diffractometer | Kuma KM4 CCD diffractometer |
Absorption correction | – | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3656, 2248, 1671 | 11922, 2058, 1229 |
Rint | 0.043 | 0.051 |
(sin θ/λ)max (Å−1) | 0.595 | 0.595 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.061, 0.170, 1.05 | 0.063, 0.158, 1.11 |
No. of reflections | 2248 | 2058 |
No. of parameters | 349 | 196 |
No. of restraints | 3 | 0 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.36, −0.20 | 0.11, −0.15 |
Absolute structure | The absolute structure was assigned according to the information
from Sigma–Aldrich. | ? |
Hydrogen-bond geometry (Å, º) for (I) top
D—H···A | D—H | H···A | D···A | D—H···A |
N1A—HN1A···O2B | 0.97 (6) | 1.92 (6) | 2.864 (5) | 166 (5) |
N1B—HN1B···O2Ai | 0.98 (6) | 1.91 (6) | 2.889 (5) | 178 (5) |
Symmetry code: (i) x, y+1, z. |
Values of the geometric parameters characteristic of a Yang photocyclization
(Å, °) top | d | D | ω | Δ | Θ |
Ideal value | <2.7 | | 0 | 90–120 | 180 |
Average literature valuea | 2.64 (8) | 3.00 (9) | 54 (10) | 82 (8) | 116 (3) |
Rangeb | 2.49–2.82 | 2.82–3.12 | 49.0–67.5 | 52.9–88.0 | 111.0–128.0 |
Average literature valuec | 2.71±0.08 | | 52.9±1.7 | 57.2±3.3 | 119.6±4.95 |
(II), this paper | 2.72 (4) | 2.857 (5) | 80.4 (10) | 58.4 (8) | 112.4 (13) |
(a) These mean values of d, ω and Δ are given for 57 and Θ for 40 aromatic
ketones undergoing a Yang photocyclization (Natarajan et al.,
2005), and
D for 53 structures (Xia et al., 2005).
(b) These ranges of the parameters are given on the basis of 47 compounds for
d, ω, Δ and Θ (Turowska-Tyrk, Bąkowicz & Scheffer, 2007;
Turowska-Tyrk,
Łabęcka, Scheffer & Xia, 2007; Turowska-Tyrk & Trzop, 2003;
Natarajan
et al., 2005; Chen et al., 2005; Ihmels &
Scheffer, 1999;
Leibovitch et al., 1998; Vishnumurthy et al.,
2002) and 15
compounds for D (Turowska-Tyrk, Bąkowicz & Scheffer, 2007;
Turowska-Tyrk,
Łabęcka, Scheffer & Xia, 2007; Turowska-Tyrk & Trzop, 2003;
Leibovitch
et al., 1998).
(c) These average values of d, ω, Δ and Θ are based on nine examples of
α-oxoamides undergoing γ-hydrogen abstraction (Natarajan et al.,
2005). |
Structural changes in crystals due to photochemical reactions are the main subject of our studies. In particular, we examine geometric changes at the reaction centre and the movement of molecules and their fragments in crystals. Studies of this type enable us to determine and understand the pathway of chemical reactions in the crystalline state and to gain knowledge of the differences and similarities that are characteristic for a given type of reaction proceeding in different compounds.
Studies of this type concern intermolecular (Fernandes & Levendis, 2004; Ohba & Ito, 2003; Turowska-Tyrk, 2001, 2003; Turowska-Tyrk & Trzop, 2003) and intramolecular photochemical reactions (Cotton et al., 2007; Turowska-Tyrk, Bąkowicz, Scheffer & Xia, 2006; Turowska-Tyrk, Trzop, Scheffer & Chen, 2006; Turowska-Tyrk, Bąkowicz & Scheffer, 2007; Turowska-Tyrk, Łabęcka, Scheffer & Xia, 2007; Trzop & Turowska-Tyrk, 2008; Zheng et al., 2007). In this paper, we present the structures of the two title compounds, (I) and (II), which can potentially undergo an intramolecular Yang photocyclization.
Compound (I) crystallizes in the triclinic space group P1 with two crystallographically independent molecules in the asymmetric unit. Fig. 1 presents projections of molecules A and B on the planes of their respective carbonyl groups, clearly showing the conformational differences. The largest difference is in the torsion angles N1—C9—C10—C11 and C16—C9—C10—C11, which are 96.2 (6) and -28.3 (7)°, respectively, for molecule A, and 37.6 (7) and -85.9 (6)°, respectively, for molecule B. Hydrogen bonds of the type N—H···O link molecules A and B into infinite chains in the b-axis direction (Fig. 2 and Table 1).
Compound (II) crystallizes in the orthorhombic space group Pbca with only one molecule in the asymmetric unit (Fig. 3). In contrast with compound (I), there are no classical hydrogen bonds. The naphthalene rings are arranged in parallel pairs, with a perpendicular distance between the rings of 3.506 (1) Å (Fig. 4).
Compounds (I) and (II) have a characteristic molecular fragment, namely the carbonyl group and a γ-H atom. Compounds with such a structure can potentially undergo an intramolecular Norrish type II photochemical reaction. A mechanism for this reaction is presented in the second scheme (Aoyama et al., 1979; Lavy et al., 2008; Yang et al., 2005). The first step is a γ-H abstraction by the carbonyl O atom and the formation of a biradical which can then undergo three reaction types: a Yang photocyclization leading to the formation of a cyclobutane ring (path a), a 1,4-hydrogen shift leading to the formation of a five-membered ring (path b) or a return to the initial reactant (path c).
Several geometric demands must be fulfilled in order that Yang photocyclization can proceed (Natarajan et al., 2005; Xia et al., 2005). They concern the following parameters: the (C)O···γ-H (d) distance, the (O)C···γC (D) distance, the deviation of γ-H from the mean plane of the carbonyl group (ω), the C═O···γ-H (Δ) angle and the γ-C—γ-H···O (Θ) angle. The ideal and average literature values for these parameters, together with the data for compound (II), are given in Table 2. For compound (I) the geometric demands are not fulfilled. The values of d and D are too large, 3.72 and 3.46 Å, respectively, which indicates the chemical inertia of compound (I) in the crystalline state. It seems that compound (II) meets the geometric demands for Yang photocyclization, although the influence of the ω parameter is not fully clear. Nevertheless, despite UV–Vis irradiation of a crystal with a 100 W Hg lamp (7 h), Yang photocyclization did not proceed. We did not observe any changes in the cell constants over the irradiation time and the structure determined after irradiation revealed only molecules of the reactant.
There can be several reasons for this inertia of compound (II). One of them was mentioned above: the value of the ω parameter differs by about 13° from the largest value observed for compounds undergoing Yang photocyclization (Turowska-Tyrk, Bąkowicz & Scheffer, 2007). Interactions between the naphthalene rings (Fig. 4) could be another cause. Such an explanation was proposed for 2,4,6-triisopropylbenzophenones (Ito et al., 2009). The next reason for the chemical inertia of (II) can be related to the size of the reaction cavity. Such a reason was given in the case of inclusion compounds (Zouev et al., 2006), styrylcoumarins (Moorthy et al., 2006) and 2,4,6-triisopropylbenzophenones (Ito et al., 1998). Interactions between naphthalene rings, as well as a small reaction cavity, restrain the molecular movements necessary for the chemical reaction to proceed. In order to make molecular movements easier, the crystal of compound (II) was irradiated at a higher temperature (323 K), but this did not help to induce a reaction. It is also possible that the photochemical reaction did not proceed owing to the absorption of UV–Vis radiation by a naphthalene group in a molecule (Natarajan et al., 2005). The lack of photochemical reaction of compound (II) cannot be a result of rotation of a methyl group because such rotation is not observed in the crystal.