Nickel‐Catalyzed Intermolecular [3+2+2] and [2+2+2] Cocyclizations of Bicyclopropylidene and Alkynes

Abstract

Abstract Under the catalysis of bis(1,5‐cyclooctadiene)nickel(0), Ni(cod) 2 , in the presence of triphenylphosphane, two molecules of bicyclopropylidene ( 1 ) and one molecule of a terminal alkyne 2 at ambient temperature undergo an intermolecular [3+2+2] cocyclization to furnish the bis‐spirocyclopropanated cyclopropylidenecycloheptene derivatives 3 in 45–93 % yield (15 examples plus 2 examples with 8 and 25 % yield, respectively). With the same catalyst system, [2+2+2] cocyclizations of two molecules of an arylmethyl (aryl=phenyl, furyl) propargyl ether and one molecule of bicyclopropylidene ( 1 ) occur to provide regioisomeric dispiro[2.0.2.4]deca‐7,9‐diene derivatives 9 / 10 (2 examples, 57 and 44 % yield, respectively).