Gold(iii) assisted C–H activation of 1,4,7-trithiacyclononane: synthesis and spontaneous resolution of a bicyclic chiral sulfonium salt†
Abstract
Reaction of [9]aneS3 (1,4,7-trithiacyclononane) with KAuCl4 in nitromethane yields the complex [Au([9]aneS3)Cl2][AuCl4]. Heating of this salt yields the bicyclic sulfonium [9]aneS3+ (4,7-dithia-1-thioniabicyclo[4,3,0]nonane) as a racemic [AuCl4]− salt. Further reaction produces [[9]aneS3+][AuCl2], which undergoes spontaneous resolution upon crystallization. Each enantiomer of [[9]aneS3+][AuCl2] was crystallographically characterized as well as the racemic [AuCl4]− salt.