Structure of methyl 2-cyano-2-(2-isopropenyl-5-methylcyclohexyl)acetate

Methyl (2RS, I'RS,2'RS,5'RS)-2-cyano2-(2'-isopropenyl-5'-methylcyclohexyl)acetate, CI4H21NO2, Mr = 235-33, monoclinic, P21/c, a = 15.631(2), b = 11.021 (1), c = 8 . 3 3 2 ( 1 ) A, /~= 92-99 (1) °, V = 1433.4 A, 3, Z = 4, Dx = 1.09 Mg m -3, A(Mo Ka) = 0.71069/~, /.t = 0-07 mm-1, F(000) = 512, T --r298 K, R = 0.053 for 1575 observed reflections. The structure was investigated to determine the relative configuration, which could not be established unambiguously by NMR. The cyclohexane ring adopts a chair conformation. There are two short intermolecular distances N(1).-.H(2a) [2.65 A (x, 0 5 y , 0 .5+z)] and H(laa).-.O(1) [2.47A ( x , 0 .5+y , 0-5-z)] . Experimental. Crystal size 0.2 x 0.6 x 0.4 mm. StoeSiemens four-circle diffractometer, profile-fitting mode involving variable scan width and speed (Clegg, 1981). 3684 reflections measured, 20max 50 °, ----h + k + l, three check reflections with no significant intensity change. 2433 unique reflections (Rin t = 0.021), of which 1575 with F > 4o(F) were used for Table 1. Atomic coordinates (x 104) and equivalent isotropic displacement parameters (A,2x 103)