16 X= l 17 X= NHNH,(excess mesyl chloride and triethylamine in THF at-50" C for 40 min) and subsequent reaction with powdered zinc iodide in methylene chloride at 23" C for 2 h (72% overall yield). Treatment of iodide 16 with excess hydrazine (97%) in 1: l dimethoxyethane-tert-butyl alcohol for 30 min at 23 OC provided the corresponding hydrazine (17, 100%) which after isolation but without purification was stirred in methylene ...
