Phosphorochloridates from phosphorohydrazides with ButOCl: stereospecificity, selectivity and phosphorylium ion intermediates

The efficiency with which a six-membered cyclic phosphorochloridate can be obtained from the corresponding hydrazide with retention of configuration at phosphorus, using tert-butyl hypochlorite in tert-butyl alcohol, depends on how stereoelectronic factors influence the fate of an intermediate chloride–phosphorylium ion pair.