Structure of (2S)-1-[(2R)-2,4-diphenyl-4-oxobutylideneamino]-2-(methoxymethyl) pyrrolidine

Abstract

Abstract Preliminary Weissenberg photographs, showed that crystals of the title compound (C22H26N2O2), belonged to the orthorhombic system with systematic absences consistent with the space group P212121. The unit-cell dimensions and their standard deviation, obtained at room temperature (293 K) were a = 10.583(6) Å, b = 18.812(2) Å, c = 9.962(1) Å, Z = 4. The unit cell volume (V) was 1983(1) Å3 and the absorption coefficient (μ) was 0.075 mm−1, D c was 1.174 and Dm measured by flotation was 1.18 Mgm−3; F(000) = 752, λ (MoKα ) = 0.7107 Å. The structure was solved by direct methods and refined by full-matrix least squares methods to a final R(F) = 0.041 and Rw(F 2) = 0.12. This work unambiguously establishes the overall conformation of the title molecule and the configuration for the new chiral centre C2 is R. The pyrrolidine ring adopts a perfect envelope 2 E conformation. Crystal cohesion is only governed by van der Waals contacts.