Crystal structure of (2RS)-2-bromomethyl-4,4-dimethyl-3,4-dihydro- 2H-pyrrole 1-oxide hemi(hydrobromide), C7H12BrNO · ½HBr

Abstract

Source of materialThe title compound has been obtained by bromocyclization of 2,2-dimethyl-4-pentenal oxime [1][2][3][4][5][6][7]. The crystallization of the product from dichloromethane furnished the title nitrone in the form of colorless crystals (m.p. 326-327 K). DiscussionIn the asymmetric unit we found one molecule of the pyrroline Noxide and half a molecule of hydrobromide, where the hydrogen H1A and the bromine ion Br2 are in special positions in the crystal with population factors of 0.5 ( figure, top). The intermolecular oxygen distance of the N-oxides is 2.429(6) Å, which is rather short. Between these oxygen atoms we found the half-populated hydrogen H1A with equal distances of 1.59(5) Å to each oxygen O1, which is very long as compared to usual O···H bonds. The O1H1A···O1 angle is 100 (4)