摘要:
The pi-type endo-cyclization of metal acetylides to form cyclohexynes was observed for the first time in the reaction of alkynylzincates derived from 5-hexynyl tosylates. The endo-cyclization took place in competition with exo-cyclization, leading to the formation of 1-(cyclopentylidene)alkylzincs. (C) 1997 Elsevier Science Ltd.