The crystal and molecular structure of the adduct from N-(4-bromobenzyl)isoquinolinium bromide and carbon disulphide

Abstract

An X-ray single-crystal structure analysis has shown that the adduct formed between N-(4-bromobenzyl)isoquinolinium bromide and carbon disulphide is 3-(p-bromophenyl)thiazolo[2,3-a]isoquinolinium-2-thione betaine. The crystals are monoclinic, a= 21·95, b= 7·19, c= 19·62 Å, β= 103° 30′, and the space group is C2/c with eight molecules in the unit cell. The structure was determined from photographic data, and the final R-factor on 1254 independent structure amplitudes was 0·08. The geometry of the mesoionic thiazolium ring system is discussed, and an explanation, involving intramolecular electrostatic forces, is advanced for the deviation of some bond angles from the normal values.