Synthesis and structural characterization of camphanates of (−)-(2S3S,3S) and (+)-(2S,3R)-4-Phenyl-3-bromo-2-butanol diastereoisomers

Abstract

The X-ray crystal structures of (−)-syn-4-phenyl-3-bromo-2-butyl camphanate (I) and (+-anti-4-phenyl-3-bromo-2-butyl camphanate (II) have been determined. Thesyn diastereoisomer of bromohydrin has the (2S,3S) absolute configuration whereas theanti diastereoisomer has the (2S,3R) absolute configuration. The crystallized derivatives I and II have been obtained by the reaction of each stereoisomer of bromohydrin, synthesized by reduction with baker's yeast, with (1S)-camphanic chloride. Crystal data: (I) C20H25BrO4:Mw: 409.32; orthorhombic,P212121;a=11.245(3),b=12.086(1),c=14.512(4) a; Z=4; finalR=0.053 for 1819 observed reflections. (II) C20H25BrO4;Mw=409.32; monoclinic, P21;a=11.352(1),b=6.378(1),c=14.255(2) a,Β=110.38(1)ℴ;Z=2; finalR=0.045 for 1672 observed reflections.