Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536803013485/dn6073sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536803013485/dn60732sup2.hkl |
CCDC reference: 199844
Key indicators
- Single-crystal X-ray study
- T = 292 K
- Mean (C-C) = 0.005 Å
- R factor = 0.053
- wR factor = 0.151
- Data-to-parameter ratio = 10.0
checkCIF results
No syntax errors found ADDSYM reports no extra symmetry
Alert Level C:
PLAT_360 Alert C Short C(sp3)-C(sp3) Bond C13 - C14 = 1.42 Ang. General Notes
REFLT_03 From the CIF: _diffrn_reflns_theta_max 27.50 From the CIF: _reflns_number_total 3001 Count of symmetry unique reflns 3040 Completeness (_total/calc) 98.72% TEST3: Check Friedels for noncentro structure Estimate of Friedel pairs measured 0 Fraction of Friedel pairs measured 0.000 Are heavy atom types Z>Si present no Please check that the estimate of the number of Friedel pairs is correct. If it is not, please give the correct count in the _publ_section_exptl_refinement section of the submitted CIF.
0 Alert Level A = Potentially serious problem
0 Alert Level B = Potential problem
1 Alert Level C = Please check
N-Fmoc-L-alanine, (1) (500 mg, 1.6 mmol), camphorsulfonic acid (325 mg, 1.4 mmol) and acetic acid (92 ml, 1.6 mmol) were dissolved in toluene (200 ml). To this solution was added n-decanal (602 ml, 3.2 mmol) and the mixture was then heated under reflux (Dean–Stark trap) for 18 h. The solution was concentrated in vacuo and the residue was taken up in ethyl acetate. The solution was then washed with 5% sodium bicarbonate solution (3 × 50 ml). The organic phase was dried (MgSO4) and concentrated in vacuo. The residue was purified by flash column chromatography, eluting with 10% ethyl acetate–hexane, to give the diastereoisomers (2) and (3) as a mixture (570 mg, 79%). A 13C NMR spectrum of the mixture indicated the ratio of compounds (2):(3) was approximately 1:2.6 (ratio obtained by integration of the methyl signals at δ 17.70 and 13.99 p.p.m., respectively). The diastereoisomers were separated by column chromatography, eluting with 25% diethyl ether–hexane. The first fraction eluted was the minor compound (2), and crystals (m.p. 350 K) were formed by slow evaporation from a solution of diethyl ether/n-hexane at room temperature.
The molecule crystallized in the non-centrosymmetric space group P21; however, owing to the absence of atom heavier than Si, the absolute configuration could not be directly determined but was deduced by reference to L-alanine. Moreover the Friedel pairs were merged and no attempt was made to refine the Flack (1983) parameter.
Data collection: SMART (Siemens, 1995); cell refinement: SAINT; data reduction: SAINT; program(s) used to solve structure: SHELXS86 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97.
C28H35NO4 | F(000) = 484 |
Mr = 449.59 | Dx = 1.171 Mg m−3 |
Monoclinic, P21 | Melting point: 350 K |
Hall symbol: P 2yb | Mo Kα radiation, λ = 0.71065 Å |
a = 5.140 (1) Å | Cell parameters from 5736 reflections |
b = 15.575 (3) Å | θ = 5–27.5° |
c = 16.050 (3) Å | µ = 0.08 mm−1 |
β = 96.995 (3)° | T = 292 K |
V = 1275.3 (4) Å3 | Tabular, colourless |
Z = 2 | 0.5 × 0.4 × 0.1 mm |
Siemens SMART CCD area-detector diffractometer | 3001 independent reflections |
Radiation source: fine-focus sealed tube | 2268 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.018 |
ω scans | θmax = 27.5°, θmin = 1.8° |
Absorption correction: multi-scan (SADABS; Blessing, 1995; Sheldrick, 1996) | h = −6→6 |
Tmin = 0.964, Tmax = 0.992 | k = −20→20 |
11309 measured reflections | l = −20→20 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.053 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.151 | H-atom parameters constrained |
S = 1.06 | w = 1/[σ2(Fo2) + (0.0928P)2 + 0.0192P] where P = (Fo2 + 2Fc2)/3 |
3001 reflections | (Δ/σ)max = 0.001 |
300 parameters | Δρmax = 0.17 e Å−3 |
1 restraint | Δρmin = −0.10 e Å−3 |
C28H35NO4 | V = 1275.3 (4) Å3 |
Mr = 449.59 | Z = 2 |
Monoclinic, P21 | Mo Kα radiation |
a = 5.140 (1) Å | µ = 0.08 mm−1 |
b = 15.575 (3) Å | T = 292 K |
c = 16.050 (3) Å | 0.5 × 0.4 × 0.1 mm |
β = 96.995 (3)° |
Siemens SMART CCD area-detector diffractometer | 3001 independent reflections |
Absorption correction: multi-scan (SADABS; Blessing, 1995; Sheldrick, 1996) | 2268 reflections with I > 2σ(I) |
Tmin = 0.964, Tmax = 0.992 | Rint = 0.018 |
11309 measured reflections |
R[F2 > 2σ(F2)] = 0.053 | 1 restraint |
wR(F2) = 0.151 | H-atom parameters constrained |
S = 1.06 | Δρmax = 0.17 e Å−3 |
3001 reflections | Δρmin = −0.10 e Å−3 |
300 parameters |
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 on F2 for ALL reflections except for 0 with very negative F2 or flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > σ(F2) is used only for calculating _ls _R_factor_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 | −0.4890 (4) | 0.63848 (16) | 0.14978 (14) | 0.0831 (6) | |
C2 | −0.2736 (5) | 0.6970 (2) | 0.16129 (19) | 0.0701 (7) | |
H2 | −0.3367 | 0.7548 | 0.1722 | 0.084* | |
N3 | −0.1156 (5) | 0.66390 (17) | 0.23598 (15) | 0.0724 (6) | |
C4 | −0.1751 (6) | 0.5742 (2) | 0.2495 (2) | 0.0802 (8) | |
H4 | −0.0426 | 0.5373 | 0.2287 | 0.096* | |
C5 | −0.4337 (7) | 0.5664 (3) | 0.1932 (2) | 0.0840 (9) | |
O5 | −0.5803 (6) | 0.5066 (2) | 0.1863 (2) | 0.1187 (10) | |
C6 | −0.2075 (8) | 0.5507 (3) | 0.3388 (3) | 0.1027 (12) | |
H6A | −0.0413 | 0.5549 | 0.3730 | 0.154* | |
H6B | −0.2721 | 0.4930 | 0.3405 | 0.154* | |
H6C | −0.3299 | 0.5893 | 0.3597 | 0.154* | |
C7 | −0.1360 (6) | 0.6977 (2) | 0.08408 (19) | 0.0700 (7) | |
H7A | −0.0912 | 0.6392 | 0.0708 | 0.084* | |
H7B | 0.0262 | 0.7297 | 0.0959 | 0.084* | |
C8 | −0.2964 (6) | 0.7367 (2) | 0.0085 (2) | 0.0761 (8) | |
H8A | −0.4611 | 0.7058 | −0.0023 | 0.091* | |
H8B | −0.3365 | 0.7958 | 0.0211 | 0.091* | |
C9 | −0.1625 (7) | 0.7347 (3) | −0.0684 (2) | 0.0884 (10) | |
H9A | −0.1280 | 0.6753 | −0.0817 | 0.106* | |
H9B | 0.0053 | 0.7634 | −0.0565 | 0.106* | |
C10 | −0.3130 (7) | 0.7761 (3) | −0.1449 (2) | 0.0874 (9) | |
H10A | −0.4846 | 0.7495 | −0.1550 | 0.105* | |
H10B | −0.3391 | 0.8362 | −0.1327 | 0.105* | |
C11 | −0.1852 (8) | 0.7699 (4) | −0.2226 (2) | 0.1066 (13) | |
H11A | −0.0116 | 0.7948 | −0.2112 | 0.128* | |
H11B | −0.1626 | 0.7095 | −0.2346 | 0.128* | |
C12 | −0.3181 (9) | 0.8107 (3) | −0.2989 (2) | 0.0971 (11) | |
H12A | −0.3306 | 0.8718 | −0.2887 | 0.117* | |
H12B | −0.4953 | 0.7883 | −0.3091 | 0.117* | |
C13 | −0.1900 (8) | 0.7981 (4) | −0.3759 (2) | 0.1059 (12) | |
H13A | −0.0114 | 0.8189 | −0.3641 | 0.127* | |
H13B | −0.1799 | 0.7368 | −0.3855 | 0.127* | |
C14 | −0.3006 (9) | 0.8364 (5) | −0.4528 (3) | 0.1256 (18) | |
H14A | −0.3081 | 0.8980 | −0.4442 | 0.151* | |
H14B | −0.4796 | 0.8162 | −0.4651 | 0.151* | |
C15 | −0.1665 (10) | 0.8209 (5) | −0.5273 (3) | 0.1304 (19) | |
H15A | 0.0189 | 0.8286 | −0.5129 | 0.196* | |
H15B | −0.2298 | 0.8607 | −0.5708 | 0.196* | |
H15C | −0.2009 | 0.7633 | −0.5469 | 0.196* | |
C16 | 0.0843 (6) | 0.7071 (2) | 0.27956 (17) | 0.0667 (7) | |
O16 | 0.2400 (5) | 0.67758 (16) | 0.33395 (14) | 0.0842 (6) | |
O17 | 0.0848 (4) | 0.78926 (14) | 0.25331 (13) | 0.0767 (6) | |
C18 | 0.2716 (6) | 0.8441 (2) | 0.30146 (19) | 0.0710 (7) | |
H18A | 0.4483 | 0.8274 | 0.2931 | 0.085* | |
H18B | 0.2538 | 0.8390 | 0.3607 | 0.085* | |
C19 | 0.2209 (6) | 0.9358 (2) | 0.2730 (2) | 0.0716 (7) | |
H19 | 0.0345 | 0.9495 | 0.2722 | 0.086* | |
C20 | 0.3848 (6) | 0.99656 (19) | 0.3316 (2) | 0.0731 (7) | |
C21 | 0.3834 (7) | 1.0102 (2) | 0.4160 (2) | 0.0840 (9) | |
H21 | 0.2649 | 0.9812 | 0.4452 | 0.101* | |
C22 | 0.5594 (8) | 1.0675 (3) | 0.4570 (3) | 0.0953 (10) | |
H22 | 0.5595 | 1.0768 | 0.5143 | 0.114* | |
C23 | 0.7307 (9) | 1.1098 (3) | 0.4152 (3) | 0.1011 (12) | |
H23 | 0.8485 | 1.1478 | 0.4442 | 0.121* | |
C24 | 0.7357 (8) | 1.0982 (3) | 0.3307 (3) | 0.0982 (11) | |
H24 | 0.8552 | 1.1279 | 0.3024 | 0.118* | |
C25 | 0.5585 (6) | 1.04125 (19) | 0.2882 (2) | 0.0745 (8) | |
C26 | 0.5114 (6) | 1.0164 (2) | 0.1989 (2) | 0.0780 (8) | |
C27 | 0.6283 (9) | 1.0427 (3) | 0.1309 (3) | 0.1006 (12) | |
H27 | 0.7650 | 1.0821 | 0.1378 | 0.121* | |
C28 | 0.5441 (10) | 1.0111 (3) | 0.0535 (3) | 0.1097 (14) | |
H28 | 0.6245 | 1.0289 | 0.0076 | 0.132* | |
C29 | 0.3386 (11) | 0.9523 (3) | 0.0421 (2) | 0.1074 (14) | |
H29 | 0.2807 | 0.9315 | −0.0112 | 0.129* | |
C30 | 0.2220 (8) | 0.9252 (2) | 0.1100 (2) | 0.0901 (10) | |
H30 | 0.0848 | 0.8859 | 0.1027 | 0.108* | |
C31 | 0.3084 (6) | 0.9561 (2) | 0.1888 (2) | 0.0723 (8) |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0674 (11) | 0.1033 (18) | 0.0771 (12) | −0.0100 (12) | 0.0032 (10) | −0.0045 (12) |
C2 | 0.0631 (15) | 0.0742 (17) | 0.0710 (17) | 0.0013 (13) | −0.0005 (13) | −0.0051 (14) |
N3 | 0.0755 (14) | 0.0694 (14) | 0.0695 (14) | −0.0071 (12) | −0.0024 (11) | 0.0066 (11) |
C4 | 0.0782 (18) | 0.0666 (17) | 0.096 (2) | −0.0030 (15) | 0.0087 (16) | 0.0034 (16) |
C5 | 0.077 (2) | 0.088 (2) | 0.087 (2) | −0.0146 (18) | 0.0116 (16) | −0.0108 (18) |
O5 | 0.1108 (19) | 0.116 (2) | 0.128 (2) | −0.0465 (19) | 0.0076 (17) | −0.0058 (18) |
C6 | 0.105 (3) | 0.098 (3) | 0.102 (3) | −0.013 (2) | −0.001 (2) | 0.031 (2) |
C7 | 0.0639 (14) | 0.0751 (17) | 0.0694 (16) | 0.0048 (14) | 0.0011 (12) | −0.0009 (14) |
C8 | 0.0748 (17) | 0.0811 (19) | 0.0709 (18) | 0.0102 (15) | 0.0028 (14) | −0.0022 (15) |
C9 | 0.0814 (19) | 0.110 (3) | 0.0728 (19) | 0.0128 (19) | 0.0050 (16) | 0.0055 (18) |
C10 | 0.097 (2) | 0.089 (2) | 0.077 (2) | 0.0184 (18) | 0.0095 (17) | 0.0056 (17) |
C11 | 0.096 (2) | 0.145 (4) | 0.080 (2) | 0.019 (3) | 0.0107 (19) | 0.011 (2) |
C12 | 0.107 (3) | 0.107 (3) | 0.077 (2) | 0.017 (2) | 0.0085 (19) | 0.0080 (19) |
C13 | 0.098 (2) | 0.133 (4) | 0.085 (2) | 0.013 (3) | 0.0011 (19) | 0.006 (2) |
C14 | 0.102 (3) | 0.187 (5) | 0.087 (3) | 0.020 (3) | 0.005 (2) | 0.028 (3) |
C15 | 0.110 (3) | 0.195 (6) | 0.086 (3) | 0.020 (3) | 0.011 (2) | 0.025 (3) |
C16 | 0.0716 (17) | 0.0676 (17) | 0.0598 (14) | −0.0037 (13) | 0.0035 (13) | 0.0009 (12) |
O16 | 0.0853 (13) | 0.0801 (14) | 0.0816 (14) | −0.0003 (11) | −0.0132 (11) | 0.0085 (11) |
O17 | 0.0826 (12) | 0.0717 (12) | 0.0705 (12) | −0.0099 (10) | −0.0115 (9) | 0.0047 (10) |
C18 | 0.0751 (17) | 0.0737 (18) | 0.0617 (15) | −0.0082 (14) | −0.0020 (13) | −0.0003 (13) |
C19 | 0.0646 (15) | 0.0734 (18) | 0.0756 (18) | 0.0027 (14) | 0.0037 (13) | −0.0034 (14) |
C20 | 0.0674 (16) | 0.0637 (16) | 0.087 (2) | 0.0063 (14) | 0.0036 (14) | −0.0016 (14) |
C21 | 0.092 (2) | 0.081 (2) | 0.079 (2) | −0.0017 (18) | 0.0104 (16) | −0.0073 (17) |
C22 | 0.113 (3) | 0.082 (2) | 0.088 (2) | −0.001 (2) | 0.000 (2) | −0.0141 (18) |
C23 | 0.107 (3) | 0.082 (2) | 0.109 (3) | −0.011 (2) | −0.007 (2) | −0.017 (2) |
C24 | 0.098 (2) | 0.077 (2) | 0.119 (3) | −0.0120 (19) | 0.010 (2) | 0.010 (2) |
C25 | 0.0771 (18) | 0.0569 (15) | 0.088 (2) | 0.0033 (13) | 0.0042 (15) | 0.0031 (14) |
C26 | 0.0803 (19) | 0.0676 (17) | 0.086 (2) | 0.0152 (15) | 0.0103 (15) | 0.0182 (15) |
C27 | 0.103 (3) | 0.103 (3) | 0.098 (3) | 0.007 (2) | 0.020 (2) | 0.022 (2) |
C28 | 0.139 (4) | 0.103 (3) | 0.092 (3) | 0.024 (3) | 0.033 (3) | 0.032 (2) |
C29 | 0.152 (4) | 0.101 (3) | 0.066 (2) | 0.035 (3) | 0.004 (2) | 0.0103 (19) |
C30 | 0.105 (2) | 0.083 (2) | 0.078 (2) | 0.0088 (19) | −0.0055 (18) | 0.0055 (17) |
C31 | 0.0758 (17) | 0.0654 (16) | 0.0739 (18) | 0.0133 (15) | 0.0020 (14) | 0.0058 (14) |
O1—C5 | 1.333 (5) | C14—H14A | 0.9700 |
O1—C2 | 1.429 (4) | C14—H14B | 0.9700 |
C2—N3 | 1.458 (4) | C15—H15A | 0.9600 |
C2—C7 | 1.500 (4) | C15—H15B | 0.9600 |
C2—H2 | 0.9800 | C15—H15C | 0.9600 |
N3—C16 | 1.350 (4) | C16—O16 | 1.202 (3) |
N3—C4 | 1.453 (4) | C16—O17 | 1.347 (4) |
C4—C6 | 1.507 (5) | O17—C18 | 1.439 (4) |
C4—C5 | 1.518 (5) | C18—C19 | 1.512 (5) |
C4—H4 | 0.9800 | C18—H18A | 0.9700 |
C5—O5 | 1.195 (5) | C18—H18B | 0.9700 |
C6—H6A | 0.9600 | C19—C31 | 1.508 (5) |
C6—H6B | 0.9600 | C19—C20 | 1.516 (4) |
C6—H6C | 0.9600 | C19—H19 | 0.9800 |
C7—C8 | 1.508 (4) | C20—C21 | 1.372 (5) |
C7—H7A | 0.9700 | C20—C25 | 1.385 (5) |
C7—H7B | 0.9700 | C21—C22 | 1.379 (5) |
C8—C9 | 1.486 (5) | C21—H21 | 0.9300 |
C8—H8A | 0.9700 | C22—C23 | 1.343 (6) |
C8—H8B | 0.9700 | C22—H22 | 0.9300 |
C9—C10 | 1.513 (5) | C23—C24 | 1.372 (6) |
C9—H9A | 0.9700 | C23—H23 | 0.9300 |
C9—H9B | 0.9700 | C24—C25 | 1.389 (5) |
C10—C11 | 1.482 (5) | C24—H24 | 0.9300 |
C10—H10A | 0.9700 | C25—C26 | 1.477 (5) |
C10—H10B | 0.9700 | C26—C27 | 1.371 (5) |
C11—C12 | 1.473 (5) | C26—C31 | 1.398 (5) |
C11—H11A | 0.9700 | C27—C28 | 1.356 (6) |
C11—H11B | 0.9700 | C27—H27 | 0.9300 |
C12—C13 | 1.482 (6) | C28—C29 | 1.394 (7) |
C12—H12A | 0.9700 | C28—H28 | 0.9300 |
C12—H12B | 0.9700 | C29—C30 | 1.372 (6) |
C13—C14 | 1.425 (6) | C29—H29 | 0.9300 |
C13—H13A | 0.9700 | C30—C31 | 1.376 (5) |
C13—H13B | 0.9700 | C30—H30 | 0.9300 |
C14—C15 | 1.471 (7) | ||
C5—O1—C2 | 110.9 (3) | H13A—C13—H13B | 106.9 |
O1—C2—N3 | 103.0 (2) | C13—C14—C15 | 117.3 (4) |
O1—C2—C7 | 109.5 (2) | C13—C14—H14A | 108.0 |
N3—C2—C7 | 114.2 (2) | C15—C14—H14A | 108.0 |
O1—C2—H2 | 109.9 | C13—C14—H14B | 108.0 |
N3—C2—H2 | 109.9 | C15—C14—H14B | 108.0 |
C7—C2—H2 | 109.9 | H14A—C14—H14B | 107.2 |
C16—N3—C4 | 124.3 (3) | C14—C15—H15A | 109.5 |
C16—N3—C2 | 124.2 (3) | C14—C15—H15B | 109.5 |
C4—N3—C2 | 110.9 (2) | H15A—C15—H15B | 109.5 |
N3—C4—C6 | 115.2 (3) | C14—C15—H15C | 109.5 |
N3—C4—C5 | 99.9 (3) | H15A—C15—H15C | 109.5 |
C6—C4—C5 | 110.9 (3) | H15B—C15—H15C | 109.5 |
N3—C4—H4 | 110.2 | O16—C16—O17 | 124.4 (3) |
C6—C4—H4 | 110.2 | O16—C16—N3 | 125.6 (3) |
C5—C4—H4 | 110.2 | O17—C16—N3 | 110.0 (2) |
O5—C5—O1 | 121.0 (4) | C16—O17—C18 | 115.0 (2) |
O5—C5—C4 | 127.8 (4) | O17—C18—C19 | 108.6 (2) |
O1—C5—C4 | 111.1 (3) | O17—C18—H18A | 110.0 |
C4—C6—H6A | 109.5 | C19—C18—H18A | 110.0 |
C4—C6—H6B | 109.5 | O17—C18—H18B | 110.0 |
H6A—C6—H6B | 109.5 | C19—C18—H18B | 110.0 |
C4—C6—H6C | 109.5 | H18A—C18—H18B | 108.3 |
H6A—C6—H6C | 109.5 | C31—C19—C18 | 114.2 (3) |
H6B—C6—H6C | 109.5 | C31—C19—C20 | 102.8 (3) |
C2—C7—C8 | 113.6 (2) | C18—C19—C20 | 109.8 (2) |
C2—C7—H7A | 108.8 | C31—C19—H19 | 109.9 |
C8—C7—H7A | 108.8 | C18—C19—H19 | 109.9 |
C2—C7—H7B | 108.8 | C20—C19—H19 | 109.9 |
C8—C7—H7B | 108.8 | C21—C20—C25 | 120.0 (3) |
H7A—C7—H7B | 107.7 | C21—C20—C19 | 129.8 (3) |
C9—C8—C7 | 113.4 (3) | C25—C20—C19 | 110.2 (3) |
C9—C8—H8A | 108.9 | C20—C21—C22 | 119.4 (4) |
C7—C8—H8A | 108.9 | C20—C21—H21 | 120.3 |
C9—C8—H8B | 108.9 | C22—C21—H21 | 120.3 |
C7—C8—H8B | 108.9 | C23—C22—C21 | 120.7 (4) |
H8A—C8—H8B | 107.7 | C23—C22—H22 | 119.7 |
C8—C9—C10 | 115.0 (3) | C21—C22—H22 | 119.7 |
C8—C9—H9A | 108.5 | C22—C23—C24 | 121.4 (4) |
C10—C9—H9A | 108.5 | C22—C23—H23 | 119.3 |
C8—C9—H9B | 108.5 | C24—C23—H23 | 119.3 |
C10—C9—H9B | 108.5 | C23—C24—C25 | 118.7 (4) |
H9A—C9—H9B | 107.5 | C23—C24—H24 | 120.7 |
C11—C10—C9 | 114.8 (3) | C25—C24—H24 | 120.7 |
C11—C10—H10A | 108.6 | C20—C25—C24 | 119.9 (3) |
C9—C10—H10A | 108.6 | C20—C25—C26 | 108.5 (3) |
C11—C10—H10B | 108.6 | C24—C25—C26 | 131.6 (3) |
C9—C10—H10B | 108.6 | C27—C26—C31 | 120.1 (4) |
H10A—C10—H10B | 107.5 | C27—C26—C25 | 131.2 (4) |
C12—C11—C10 | 117.7 (3) | C31—C26—C25 | 108.7 (3) |
C12—C11—H11A | 107.9 | C28—C27—C26 | 119.9 (4) |
C10—C11—H11A | 107.9 | C28—C27—H27 | 120.1 |
C12—C11—H11B | 107.9 | C26—C27—H27 | 120.1 |
C10—C11—H11B | 107.9 | C27—C28—C29 | 120.7 (4) |
H11A—C11—H11B | 107.2 | C27—C28—H28 | 119.6 |
C11—C12—C13 | 115.4 (4) | C29—C28—H28 | 119.6 |
C11—C12—H12A | 108.4 | C30—C29—C28 | 119.7 (4) |
C13—C12—H12A | 108.4 | C30—C29—H29 | 120.2 |
C11—C12—H12B | 108.4 | C28—C29—H29 | 120.2 |
C13—C12—H12B | 108.4 | C29—C30—C31 | 119.9 (4) |
H12A—C12—H12B | 107.5 | C29—C30—H30 | 120.0 |
C14—C13—C12 | 119.8 (4) | C31—C30—H30 | 120.0 |
C14—C13—H13A | 107.4 | C30—C31—C26 | 119.6 (3) |
C12—C13—H13A | 107.4 | C30—C31—C19 | 130.7 (3) |
C14—C13—H13B | 107.4 | C26—C31—C19 | 109.7 (3) |
C12—C13—H13B | 107.4 |
Experimental details
Crystal data | |
Chemical formula | C28H35NO4 |
Mr | 449.59 |
Crystal system, space group | Monoclinic, P21 |
Temperature (K) | 292 |
a, b, c (Å) | 5.140 (1), 15.575 (3), 16.050 (3) |
β (°) | 96.995 (3) |
V (Å3) | 1275.3 (4) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.5 × 0.4 × 0.1 |
Data collection | |
Diffractometer | Siemens SMART CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Blessing, 1995; Sheldrick, 1996) |
Tmin, Tmax | 0.964, 0.992 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 11309, 3001, 2268 |
Rint | 0.018 |
(sin θ/λ)max (Å−1) | 0.650 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.053, 0.151, 1.06 |
No. of reflections | 3001 |
No. of parameters | 300 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.17, −0.10 |
Computer programs: SMART (Siemens, 1995), SAINT, SHELXS86 (Sheldrick, 1990), SHELXL97 (Sheldrick, 1997), ORTEPII (Johnson, 1976), SHELXL97.
Subscribe to Acta Crystallographica Section E: Crystallographic Communications
The full text of this article is available to subscribers to the journal.
- Information on subscribing
- Sample issue
- If you have already subscribed, you may need to register
In the course of preparation of an N-alkyl-L-alanine derivative, the intermediate (1) was treated with n-decanal and camphorsulfonic acid in refluxing toluene. The reaction gave two diastereoisomeric 5-oxazolidinones, (2) and (3), as products in which the molecules have either trans- or cis-configured n-nonyl and methyl substituents about the 5-oxazolidinone ring. Other workers have prepared similar structures in studies concerned with the manipulation of α-amino acids generally for the construction of α,α-dialky-α-amino acids (see, for example, Karady et al., 1984). Compounds (2) and (3) were separated by column chromatography. As the 1H NMR spectra of both compounds were similar we were unable to determine the configuration at the C2 asymmetric center, the S configuration being assigned to C4 with reference to L-alanine. Following column chromatography, the minor diastereoisomer crystallized and so an X-ray analysis was undertaken to ascertain its structure as either (2) or (3).
As structure (2) was found to have trans-configured n-nonyl and methyl substituents about the 5-oxazolidinone ring (Fig. 1), the configuration at C2 is R. The nonyl side chain at C2 is fully extended, the pertinent angles ranging from 176.9 (3) to 179.6 (4)°. The oxazolidinone ring adopts a half-chair conformation as indicated by the pseudo-rotation parameters (Altona et al., 1968) Δ = 1.5 and ϕm 21.1°. The fluorenyl substituent at C18 is not strictly planar as is generally observed for other fluorenyl moieties, but rather exhibits a slight bowing of the rings. The mean plane through the thirteen atoms shows that only five atoms C19, C21, C22, C29 and C30 lie −0.070 (3), 0.037 (3), 0.042 (3), 0.045 (4) and 0.032 (3) Å, respectively, from the plane whilst the other eight atoms lie roughly in the plane (r.m.s.d. < 0.02 Å). This characteristic, athough more pronounced, has been noted recently in another crystal structure containing a fluorenyl moiety (Meyers et al., 2001). The other dimensions associated with the central five-membered ring are similar to those generally observed for other comparable structures.
The crystal packing illustrated in Fig. 2 shows that the molecules are orientated in the crystal with the linear n-nonyl groups aligned along the b-crystal axis and adjacent to the fluorenyl moieties of adjacent molecules. Some intermolecular interaction between the two groups could account for the slight bowing of the fluorenyl rings. Intermolecular interactions also were suggested as causing this effect noticed previously.