Facile formation of iodocyclobutenes by a ruthenium-catalyzed enyne cycloisomerization

摘要

Enynes bearing an iodide (bromide) at their alkyne terminus react with catalytic amounts of [Cp~*Ru(MeCN)_3]PF_6 in DMF to give strained iodo(bromo)cyclobutene derivatives in good to excellent yields.