Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270106049018/gd3062sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270106049018/gd3062Isup2.hkl |
CCDC reference: 632941
Analytical grade reagent L-phenylalanine (Aldrich) and 4-nitrophenol (Aldrich) were dissolved separately in water and methanol, respectively. The solutions were then added in a 1:1 molar ratio and stirred at 323 K for several hours; the resulting solution was allowed to cool to room temperature and crystals were obtained after two weeks, by slow evaporation at room temperature. A suitable crystal was selected and checked by photographic methods before data collection.
All H atoms were placed at geometrically idealized positions and refined as riding [C—H = 0.97, 0.98 and 0.93 Å for secondary CH2, tertiary CH and aromatic CH respectively; O—H = 0.82 Å; N—H = 0.89 Å; Uiso(H) = 1.2Ueq(C) and Uiso(H) = 1.5Ueq(O,N)]. Examination of the crystal structure with PLATON (Spek, 2003) showed that there are no solvent-accessible voids in the crystal lattice.
Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software; data reduction: PLATON (Spek, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97.
C9H11NO2·C6H5NO3 | F(000) = 320 |
Mr = 304.30 | Dx = 1.387 Mg m−3 |
Monoclinic, P21 | Cu Kα radiation, λ = 1.54184 Å |
Hall symbol: P 2yb | Cell parameters from 25 reflections |
a = 5.8327 (2) Å | θ = 18.7–26.6° |
b = 7.0099 (9) Å | µ = 0.89 mm−1 |
c = 17.8751 (4) Å | T = 295 K |
β = 94.59 (10)° | Rod, clear colourless |
V = 728.51 (14) Å3 | 0.34 × 0.17 × 0.17 mm |
Z = 2 |
Enraf–Nonius CAD-4 diffractometer | 2770 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.024 |
Graphite monochromator | θmax = 72.4°, θmin = 5.0° |
Profile data from ω–2θ scans | h = −7→7 |
Absorption correction: ψ scan (North et al., 1968) | k = −8→8 |
Tmin = 0.72, Tmax = 0.86 | l = 0→22 |
2983 measured reflections | 3 standard reflections every 180 min |
2894 independent reflections | intensity decay: 4% |
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.042 | w = 1/[σ2(Fo2) + (0.0909P)2 + 0.1548P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.140 | (Δ/σ)max < 0.001 |
S = 1.17 | Δρmax = 0.20 e Å−3 |
2894 reflections | Δρmin = −0.23 e Å−3 |
202 parameters | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
1 restraint | Extinction coefficient: 0.018 (2) |
Primary atom site location: structure-invariant direct methods | Absolute structure: Flack (1983), 1320 Friedel pairs |
Secondary atom site location: difference Fourier map | Absolute structure parameter: −0.2 (2) |
C9H11NO2·C6H5NO3 | V = 728.51 (14) Å3 |
Mr = 304.30 | Z = 2 |
Monoclinic, P21 | Cu Kα radiation |
a = 5.8327 (2) Å | µ = 0.89 mm−1 |
b = 7.0099 (9) Å | T = 295 K |
c = 17.8751 (4) Å | 0.34 × 0.17 × 0.17 mm |
β = 94.59 (10)° |
Enraf–Nonius CAD-4 diffractometer | 2770 reflections with I > 2σ(I) |
Absorption correction: ψ scan (North et al., 1968) | Rint = 0.024 |
Tmin = 0.72, Tmax = 0.86 | 3 standard reflections every 180 min |
2983 measured reflections | intensity decay: 4% |
2894 independent reflections |
R[F2 > 2σ(F2)] = 0.042 | H-atom parameters constrained |
wR(F2) = 0.140 | Δρmax = 0.20 e Å−3 |
S = 1.17 | Δρmin = −0.23 e Å−3 |
2894 reflections | Absolute structure: Flack (1983), 1320 Friedel pairs |
202 parameters | Absolute structure parameter: −0.2 (2) |
1 restraint |
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. |
x | y | z | Uiso*/Ueq | ||
O1 | −0.2825 (2) | 0.7639 (2) | 0.45893 (9) | 0.0372 (4) | |
O2 | −0.1545 (2) | 0.5043 (2) | 0.40292 (8) | 0.0375 (4) | |
C1 | −0.1269 (3) | 0.6604 (3) | 0.43587 (10) | 0.0279 (4) | |
C2 | 0.1199 (3) | 0.7345 (3) | 0.45020 (10) | 0.0273 (4) | |
H2 | 0.1439 | 0.7728 | 0.5030 | 0.033* | |
N1 | 0.2852 (3) | 0.5779 (3) | 0.43657 (10) | 0.0308 (4) | |
H1A | 0.2710 | 0.4850 | 0.4698 | 0.046* | |
H1B | 0.4281 | 0.6233 | 0.4414 | 0.046* | |
H1C | 0.2549 | 0.5322 | 0.3904 | 0.046* | |
C3 | 0.1629 (3) | 0.9091 (3) | 0.40118 (12) | 0.0327 (4) | |
H3A | 0.0707 | 1.0146 | 0.4170 | 0.039* | |
H3B | 0.3233 | 0.9458 | 0.4097 | 0.039* | |
C4 | 0.1078 (4) | 0.8773 (3) | 0.31796 (11) | 0.0301 (4) | |
C5 | −0.1050 (4) | 0.9318 (3) | 0.28386 (13) | 0.0364 (5) | |
H5 | −0.2147 | 0.9847 | 0.3126 | 0.044* | |
C6 | −0.1545 (4) | 0.9077 (4) | 0.20751 (14) | 0.0430 (5) | |
H6 | −0.2975 | 0.9441 | 0.1853 | 0.052* | |
C7 | 0.0068 (5) | 0.8299 (4) | 0.16408 (13) | 0.0435 (5) | |
H7 | −0.0262 | 0.8151 | 0.1126 | 0.052* | |
C8 | 0.2178 (4) | 0.7743 (4) | 0.19757 (13) | 0.0421 (5) | |
H8 | 0.3265 | 0.7205 | 0.1686 | 0.051* | |
C9 | 0.2685 (4) | 0.7982 (3) | 0.27410 (12) | 0.0352 (5) | |
H9 | 0.4113 | 0.7608 | 0.2961 | 0.042* | |
O3 | 0.4867 (3) | 0.3450 (3) | 0.32340 (9) | 0.0422 (4) | |
H3 | 0.6051 | 0.3842 | 0.3461 | 0.063* | |
C10 | 0.5145 (4) | 0.3399 (3) | 0.24837 (11) | 0.0325 (5) | |
C11 | 0.7123 (4) | 0.4079 (4) | 0.21995 (13) | 0.0388 (5) | |
H11 | 0.8290 | 0.4614 | 0.2518 | 0.047* | |
C12 | 0.7349 (4) | 0.3956 (4) | 0.14368 (14) | 0.0434 (5) | |
H12 | 0.8682 | 0.4381 | 0.1237 | 0.052* | |
C13 | 0.5574 (5) | 0.3195 (4) | 0.09767 (13) | 0.0431 (5) | |
N2 | 0.5863 (6) | 0.3064 (5) | 0.01739 (14) | 0.0678 (8) | |
O4 | 0.7756 (6) | 0.3292 (8) | −0.00318 (16) | 0.1207 (16) | |
O5 | 0.4196 (6) | 0.2717 (7) | −0.02521 (13) | 0.1035 (12) | |
C14 | 0.3574 (4) | 0.2539 (4) | 0.12497 (14) | 0.0448 (6) | |
H14 | 0.2395 | 0.2040 | 0.0927 | 0.054* | |
C15 | 0.3358 (4) | 0.2639 (4) | 0.20120 (13) | 0.0387 (5) | |
H15 | 0.2027 | 0.2201 | 0.2210 | 0.046* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0221 (6) | 0.0489 (9) | 0.0410 (8) | 0.0024 (6) | 0.0045 (5) | −0.0029 (7) |
O2 | 0.0318 (7) | 0.0420 (8) | 0.0376 (8) | −0.0051 (7) | −0.0035 (6) | −0.0039 (7) |
C1 | 0.0228 (8) | 0.0367 (10) | 0.0235 (8) | −0.0013 (8) | −0.0018 (6) | 0.0038 (8) |
C2 | 0.0203 (8) | 0.0356 (10) | 0.0258 (8) | 0.0000 (7) | 0.0005 (6) | −0.0017 (7) |
N1 | 0.0220 (7) | 0.0371 (8) | 0.0330 (8) | 0.0017 (7) | 0.0006 (6) | −0.0009 (7) |
C3 | 0.0280 (9) | 0.0339 (10) | 0.0359 (10) | −0.0035 (8) | 0.0006 (8) | −0.0018 (8) |
C4 | 0.0287 (9) | 0.0300 (9) | 0.0316 (10) | −0.0021 (7) | 0.0036 (7) | 0.0048 (8) |
C5 | 0.0280 (10) | 0.0412 (11) | 0.0402 (11) | 0.0024 (8) | 0.0043 (8) | 0.0063 (9) |
C6 | 0.0353 (11) | 0.0500 (13) | 0.0422 (12) | −0.0038 (10) | −0.0062 (9) | 0.0102 (10) |
C7 | 0.0535 (13) | 0.0446 (12) | 0.0319 (10) | −0.0102 (11) | −0.0001 (9) | 0.0040 (9) |
C8 | 0.0481 (13) | 0.0427 (12) | 0.0369 (11) | 0.0017 (10) | 0.0120 (9) | 0.0015 (10) |
C9 | 0.0296 (10) | 0.0389 (11) | 0.0376 (10) | 0.0033 (8) | 0.0056 (8) | 0.0046 (9) |
O3 | 0.0372 (8) | 0.0555 (10) | 0.0337 (8) | −0.0049 (7) | 0.0023 (6) | −0.0079 (7) |
C10 | 0.0312 (10) | 0.0338 (11) | 0.0322 (10) | 0.0009 (8) | 0.0003 (8) | −0.0023 (8) |
C11 | 0.0345 (11) | 0.0419 (12) | 0.0393 (11) | −0.0042 (9) | −0.0006 (9) | −0.0059 (9) |
C12 | 0.0420 (12) | 0.0491 (13) | 0.0400 (12) | −0.0050 (10) | 0.0091 (9) | −0.0002 (10) |
C13 | 0.0549 (13) | 0.0433 (12) | 0.0313 (11) | 0.0000 (11) | 0.0035 (9) | −0.0001 (9) |
N2 | 0.090 (2) | 0.0775 (19) | 0.0361 (12) | −0.0073 (16) | 0.0036 (12) | −0.0016 (12) |
O4 | 0.110 (2) | 0.204 (5) | 0.0529 (14) | −0.035 (3) | 0.0366 (15) | −0.014 (2) |
O5 | 0.113 (2) | 0.156 (3) | 0.0384 (11) | −0.020 (2) | −0.0137 (13) | −0.0094 (16) |
C14 | 0.0449 (12) | 0.0469 (13) | 0.0407 (12) | −0.0061 (11) | −0.0091 (9) | −0.0048 (11) |
C15 | 0.0324 (10) | 0.0413 (11) | 0.0418 (11) | −0.0045 (9) | −0.0004 (8) | −0.0007 (10) |
O1—C1 | 1.257 (3) | C7—H7 | 0.9300 |
O2—C1 | 1.247 (3) | C8—C9 | 1.387 (3) |
C1—C2 | 1.533 (2) | C8—H8 | 0.9300 |
C2—N1 | 1.494 (3) | C9—H9 | 0.9300 |
C2—C3 | 1.538 (3) | O3—C10 | 1.364 (3) |
C2—H2 | 0.9800 | O3—H3 | 0.8200 |
N1—H1A | 0.8900 | C10—C11 | 1.382 (3) |
N1—H1B | 0.8900 | C10—C15 | 1.393 (3) |
N1—H1C | 0.8900 | C11—C12 | 1.383 (3) |
C3—C4 | 1.513 (3) | C11—H11 | 0.9300 |
C3—H3A | 0.9700 | C12—C13 | 1.377 (4) |
C3—H3B | 0.9700 | C12—H12 | 0.9300 |
C4—C9 | 1.385 (3) | C13—C14 | 1.379 (4) |
C4—C5 | 1.392 (3) | C13—N2 | 1.461 (3) |
C5—C6 | 1.383 (3) | N2—O4 | 1.202 (4) |
C5—H5 | 0.9300 | N2—O5 | 1.211 (4) |
C6—C7 | 1.379 (4) | C14—C15 | 1.380 (3) |
C6—H6 | 0.9300 | C14—H14 | 0.9300 |
C7—C8 | 1.381 (4) | C15—H15 | 0.9300 |
O2—C1—O1 | 126.32 (19) | C6—C7—H7 | 120.3 |
O2—C1—C2 | 117.41 (18) | C8—C7—H7 | 120.3 |
O1—C1—C2 | 116.27 (18) | C7—C8—C9 | 120.4 (2) |
N1—C2—C1 | 109.47 (16) | C7—C8—H8 | 119.8 |
N1—C2—C3 | 110.79 (16) | C9—C8—H8 | 119.8 |
C1—C2—C3 | 111.64 (16) | C4—C9—C8 | 120.4 (2) |
N1—C2—H2 | 108.3 | C4—C9—H9 | 119.8 |
C1—C2—H2 | 108.3 | C8—C9—H9 | 119.8 |
C3—C2—H2 | 108.3 | C10—O3—H3 | 109.5 |
C2—N1—H1A | 109.5 | O3—C10—C11 | 121.4 (2) |
C2—N1—H1B | 109.5 | O3—C10—C15 | 117.6 (2) |
H1A—N1—H1B | 109.5 | C11—C10—C15 | 121.0 (2) |
C2—N1—H1C | 109.5 | C10—C11—C12 | 119.3 (2) |
H1A—N1—H1C | 109.5 | C10—C11—H11 | 120.4 |
H1B—N1—H1C | 109.5 | C12—C11—H11 | 120.4 |
C4—C3—C2 | 114.30 (17) | C13—C12—C11 | 119.1 (2) |
C4—C3—H3A | 108.7 | C13—C12—H12 | 120.4 |
C2—C3—H3A | 108.7 | C11—C12—H12 | 120.4 |
C4—C3—H3B | 108.7 | C12—C13—C14 | 122.3 (2) |
C2—C3—H3B | 108.7 | C12—C13—N2 | 118.1 (2) |
H3A—C3—H3B | 107.6 | C14—C13—N2 | 119.6 (2) |
C9—C4—C5 | 118.8 (2) | O4—N2—O5 | 123.1 (3) |
C9—C4—C3 | 121.02 (19) | O4—N2—C13 | 118.2 (3) |
C5—C4—C3 | 120.1 (2) | O5—N2—C13 | 118.7 (3) |
C6—C5—C4 | 120.5 (2) | C13—C14—C15 | 118.6 (2) |
C6—C5—H5 | 119.8 | C13—C14—H14 | 120.7 |
C4—C5—H5 | 119.8 | C15—C14—H14 | 120.7 |
C7—C6—C5 | 120.4 (2) | C14—C15—C10 | 119.6 (2) |
C7—C6—H6 | 119.8 | C14—C15—H15 | 120.2 |
C5—C6—H6 | 119.8 | C10—C15—H15 | 120.2 |
C6—C7—C8 | 119.5 (2) | ||
O2—C1—C2—N1 | −13.2 (2) | C7—C8—C9—C4 | 0.3 (3) |
O1—C1—C2—N1 | 166.64 (17) | O3—C10—C11—C12 | 178.5 (2) |
O2—C1—C2—C3 | 109.9 (2) | C15—C10—C11—C12 | −1.7 (4) |
O1—C1—C2—C3 | −70.3 (2) | C10—C11—C12—C13 | 1.4 (4) |
N1—C2—C3—C4 | 67.5 (2) | C11—C12—C13—C14 | −0.4 (4) |
C1—C2—C3—C4 | −54.8 (2) | C11—C12—C13—N2 | −179.4 (3) |
C2—C3—C4—C9 | −85.6 (2) | C12—C13—N2—O4 | 13.3 (5) |
C2—C3—C4—C5 | 95.9 (2) | C14—C13—N2—O4 | −165.8 (4) |
C9—C4—C5—C6 | −0.2 (3) | C12—C13—N2—O5 | −167.3 (4) |
C3—C4—C5—C6 | 178.3 (2) | C14—C13—N2—O5 | 13.6 (5) |
C4—C5—C6—C7 | −0.2 (4) | C12—C13—C14—C15 | −0.5 (4) |
C5—C6—C7—C8 | 0.7 (4) | N2—C13—C14—C15 | 178.6 (3) |
C6—C7—C8—C9 | −0.7 (4) | C13—C14—C15—C10 | 0.2 (4) |
C5—C4—C9—C8 | 0.2 (3) | O3—C10—C15—C14 | −179.3 (2) |
C3—C4—C9—C8 | −178.4 (2) | C11—C10—C15—C14 | 0.8 (4) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O1i | 0.89 | 2.00 | 2.887 (2) | 172 |
N1—H1B···O1ii | 0.89 | 1.96 | 2.838 (2) | 170 |
N1—H1C···O3 | 0.89 | 2.29 | 2.919 (3) | 128 |
O3—H3···O2ii | 0.82 | 1.87 | 2.678 (3) | 171 |
Symmetry codes: (i) −x, y−1/2, −z+1; (ii) x+1, y, z. |
Experimental details
Crystal data | |
Chemical formula | C9H11NO2·C6H5NO3 |
Mr | 304.30 |
Crystal system, space group | Monoclinic, P21 |
Temperature (K) | 295 |
a, b, c (Å) | 5.8327 (2), 7.0099 (9), 17.8751 (4) |
β (°) | 94.59 (10) |
V (Å3) | 728.51 (14) |
Z | 2 |
Radiation type | Cu Kα |
µ (mm−1) | 0.89 |
Crystal size (mm) | 0.34 × 0.17 × 0.17 |
Data collection | |
Diffractometer | Enraf–Nonius CAD-4 diffractometer |
Absorption correction | ψ scan (North et al., 1968) |
Tmin, Tmax | 0.72, 0.86 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2983, 2894, 2770 |
Rint | 0.024 |
(sin θ/λ)max (Å−1) | 0.618 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.042, 0.140, 1.17 |
No. of reflections | 2894 |
No. of parameters | 202 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.20, −0.23 |
Absolute structure | Flack (1983), 1320 Friedel pairs |
Absolute structure parameter | −0.2 (2) |
Computer programs: CAD-4 Software (Enraf–Nonius, 1989), CAD-4 Software, PLATON (Spek, 2003), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), ORTEPII (Johnson, 1976), SHELXL97.
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O1i | 0.89 | 2.00 | 2.887 (2) | 172 |
N1—H1B···O1ii | 0.89 | 1.96 | 2.838 (2) | 170 |
N1—H1C···O3 | 0.89 | 2.29 | 2.919 (3) | 128 |
O3—H3···O2ii | 0.82 | 1.87 | 2.678 (3) | 171 |
Symmetry codes: (i) −x, y−1/2, −z+1; (ii) x+1, y, z. |
Compounds containing amino acids and other molecules or ions have drawn a lot of attention because of the potential applications in domains such as pharmaceutical drugs, nonlinear optics and biochemistry. Much information has thus been gathered on these materials regarding properties such as aggregation patterns, conformational effects caused by the presence of other molecules or ions, nonlinear optical behaviour, ferroelastic/electric properties and phase diagrams. Furthermore, molecules containing π-electron bonds, unbalanced by the presence of polar groups and capable of accepting or giving electrons, are highly polarizable (Pecaut & Bagieu-Beucher, 1993); nitrophenols can also act as π acceptors with other aromatic molecules as well as acidic ligands forming co-compounds/salts through strong hydrogen bonding (In et al., 1997). The synthesis of the title compound has been undertaken in order to obtain a material with strong second harmonic generation properties. However, the non-linear optical properties of L-phenylalanine–4-nitrophenol (LPA–PN) were found to be rather weak in comparison to urea.
The LPA molecule is in the neutral zwitterionic state with a protonated amino group positively charged and a negatively charged carboxyl group. The conformation of this amino acid is described by the torsion angles χ1 = 67.5 (2)° and χ21 = 95.9 (2)° (IUPAC–IUB Commission on Biochemical Nomenclature, 1970); the χ1 value corresponds to a sterically less favoured G+ conformation already found in L-phenylalaninium L-phenylalanine perchlorate (Srinivasan & Rajaram, 1997) and the χ21 angle is indicative of a folded conformation.
The PN molecule shows typical bond lengths and angles (Coppens & Schmidt, 1965). The whole molecule is nearly planar, with the expected small deviations of the nitro and hydroxy O atoms. The latter are deviated towards the same side of the ring plane; one of O atoms of the nitro group lies slightly above the ring plane, whereas the other is positioned below the ring. Asymmetry between the two C—C—O angles due to the repulsion between the H atom and the C atom carrying the hydroxyl group (Hirshfeld, 1964) is also present.
The LPA molecules are bonded to each other via the strong N1—H1B···O1ii hydrogen bond [symmetry code: (ii) x + 1, y, z], forming C(5) chains (Grell et al., 1999) running along the a axis (Fig. 2). These chains are interlinked through additional hydrogen bonds giving rise to hydrophilic sheets parallel to the (001) planes; these sheets are formed by the [100] chains of the LPA molecules and the hydroxy groups of the PN molecules. In each of these sheets the hydrogen bonds N1—H1B···O1ii, O3—H3···O2ii and N1—H1C···O3 generate an R33(8) ring; the bonds N1—H1A···O1i, O3—H3···O2ii and N1—H1C···O3 [symmetry code: (i) −x, y − 1/2, −z + 1] generate an R55(16) ring; and N1—H1B···O1ii and N1—H1A···O1i give rise to an R43(14) ring.
In the hydrogen-bonding scheme, atom N1 acts as the centre of a set of trifurcated donor bonds, atom O1 is the acceptor of two (bifurcated) bonds, whereas atom O3 acts simultaneously as the acceptor of one bond and donor of another. The aromatic rings of both the LPA and the NP molecules border the hydrophilic layers, forming hydrophobic coatings on both sides of the layers. The slabs, made of a central hydrophilic layer and two bordering hydrophobic aromatic ring layers, are repeated along the [001] direction and bond to each other through van der Waals interactions, leading to alternating hydrophilic and hydrophobic zones.