Structure of (S)-(+)-ibuprofen

Abstract

(S)-(+)-Ibuprofen, α-methyl-4-(2-methylpropyl)benzeneacetic acid, crystallizes with two molecules in the asymmetric unit to form a cyclic hydrogenbonded dimer. Within the dimer each molecule shows subtle conformational differences via rotations about the acetic C(1)-C(2) and C(10)-C(11) bonds. Bond distances and angles for (S)-(+)-ibuprofen are in close agreement with those found for the structure of the racemic compound [McConnell (1914). Cryst. Struct. Commun. 3, 13-15]