Gold-catalyzed reactions of conjugated haloacetylenes are well known and usually result
in the formation of addition or dimerization products. Herein, we report a gold-catalyzed
reaction of non-conjugated haloacetylenes, which leads exclusively to the halogenated
cyclization products. Remarkable is the gold-catalyzed reaction of tritylhaloacetylenes
to haloindene derivatives, as mechanistic studies reveal that an 1,2-aryl shift occurs
in the initially formed gold complex. The potential functionalization at the halogen
atom and the wide scope of these cyclization reactions make them an attractive method
for the construction of cyclic systems.
Key words
gold catalysis - haloacetylenes - indene - chromene - chromane - 1,2-aryl shift -
cyclization