N-{2-[(1-Cyanocyclohexyl)(tert-butyldimethylsilyloxy)amino]propionyl}-2,5-bis(methoxymethyl)pyrrolidine and N-(2-anilinopropionyl)-2,5-bis(methoxymethyl)pyrrolidine

Abstract

(1): C24H45N3O4Si, M(r) = 467.73, monoclinic, P2(1)/c, a = 12.947 (3), b = 13.814 (4), c = 16.186 (5) angstrom, beta = 108.61 (3)-degrees, V = 2744 (1) angstrom 3, Z = 4, D(x) = 1.13 g cm-3, Cu K-alpha, lambda = 1.5418 angstrom, mu = 9.90 cm-1, F(000) = 1024, T = 291 K, R = 0.058 for 4276 observed reflections. (2): C17H26N2O3, M(r) = 306.41, monoclinic, P2(1)/c, a = 9.579 (2), b = 9.601 (1), c = 18.826 (2) angstrom, beta = 103.25 (2)-degrees, V = 1685.3 (4) angstrom 3, Z = 4, D(x) = 1.21 g cm-3, Mo K-alpha, lambda = 0.71069 angstrom, mu = 0.89 cm-1, F(000) = 664, T = 291 K, R = 0.042 for 2361 observed reflections. The relative configuration of the propionyl asymmetric carbon is inverse with respect to that of the pyrrolidine ring carbon atoms (i.e. one is R and the other S). The conformation of the pyrrolidine is different in the two compounds: in (1), it is an envelope with torsion angles of 23.0 (6), -36.0 (6), 36.5 (6), -22.2 (6) and 0.0 (6)-degrees; in (2), it adopts a half-chair conformation with the twofold axis through N, the endocyclic torsion angles being 8.8 (5), -27.7 (5), 36.5 (5), -30.3 (5) and 13.4 (5)-degrees. In (2), an intermolecular hydrogen bond between the N-H and the carbonyl O is observed: N-H...O, N...O = 3.098 (3), H...O = 2.24 (2) angstrom, N-H...O = 175 (1)-degrees (O: 1 - x, -y, 1 - z).