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Lipase-catalyzed kinetic resolution of alcohols via chloroacetate esters: (−)-(1R,2S)-trans-2-phenylcyclohexanol and (+)-(1S,2R)-trans-2-phenylcyclohexanol intermediate: 100 g (0.567 mol) of racemic trans-2-phenylcyclohexanol intermediate: racemic trans-2-phenylcyclohexyl chloroacetate product: (−)-(1R,2S)-trans-2-phenylcyclohexanol byproduct: (−)-(1S,2R)-trans-2-phenylcyclohexyl chloroacetate byproduct: (−)-(1R,2S)-trans-2-phenylcyclohexanol product: (+)-(1S,2R)-trans-2-phenylcyclohexanol Keywords: acylation; enzymatic reactions; esterification, of substituted monobasic acids; hydrolysis, esters and lactones; ring opening reactions; assay methods, of enantiomeric purity of alcohols by NMR analysis of mosher esters; benzene; chloroacetyl chloride, lachrymator; dimethylaniline, poison; pH controller

3aR-(3aα4aβ7aβ7bα)

R-octahydro-3aα, 4aβ, 7aβ, 7bα (nitro-4 phenyl)-4 1H, 5H-dicyclopenta [b, d] pyrrole, C 16 H 20 N 2 O 2 , cristallise dans P2 1 2 1 2 1 avec a=8,696, b=9,630 et c=16,428 A, Z=4; affinement jusqu'a R=0,0409. La chiralite cristalline correspond a la chiralite commune de l'amine parent. Des paires de molecules voisines s'empilent en un arrangement tete-a-queue avec un centre de pseudo-inversion

trans-2-Phenylcyclohexyl N-(5-isopropenyl-2-methyl-2-cyclohexan-1-yl) carbamate, C23H31NO2, Mr = 353.50, orthorhombic, P2(1)2(1)2(1), a = 8.813 (2), b = 9.043 (2), c = 25.643 (5) A, V = 2043.6 (8) A3, Z = 4, Dx = 1.15 g cm-3 (198 K), Mo K alpha radiation, lambda = 0.7107 A, mu = 0.6734 cm-1, F(000) = 768, T = 198 K, R = 0.0547 for 1772 reflections [Fo greater than or equal to 4 sigma(Fo)]. Molecules are H-bonded into infinite columns parallel to a. The H bond involves the NH group and the carbonyl O atom of the carbamate moiety with relevant parameters: N11-H11...O13 (related by 1/2 + x, 1/2 - y, - z); N...O 2.910 (5), H...O 2.11 (5) A, N-H...O 159 (4) degrees.

The title compound, C35H34O6, crystallizes with two independent molecules per asymmetric unit. The molecules assume slightly different conformations. The crystallographically unique molecules stack in columns along the b axis. Close C—H⋯O contacts are observed between molecules related by a twofold screw axis. Such contacts are: C35—H35⋯O40 (related by 2 − x, {1\over 2} + y, −1 − z), C⋯O 3.440 (5) A; H⋯O 2.553 (5) A; C—H⋯O 153.7 (1)° for molecule 1 and: C33′-H33′⋯O40′ (related by 1 − x, −{1\over 2} + y, 1 − z); C⋯O 3.422 (5) A, H⋯O 2.491 (5) A, 163.3 (1)° for molecule 2. The absolute configuration was established by internal comparison to the (R)-(−)-O-methyl mandelic acid moiety.