Crystal and molecular structure of 5-chloro-2,1-benzisothiazole

Abstract

The crystal and molecular structure of the title compound has been determined by X-ray crystallographic analysis from diffractometer data. The crystals belong to the orthorhombic space group P2₁2₁2₁, with a= 3·926, b= 9·928, c= 18·204 Å and Z= 4. The structure was solved by the heavy-atom method, and refined by Fourier and least-squares procedures to a final R of 0·035 with 475 observed terms. The molecule is planar to within ±0·014 Å, and the C–S and N–S bond lengths are 1·664 ± 0·005 and 1·636 ± 0·005 Å respectively. These dimensions and others indicate considerable π electron delocalization extending throughout the two fused rings. N.m.r. evidence is also reported.