Reaction of a double bond of zirconacyclopentadienes: formation of 1,2,3,5-tetrasubstituted benzenes via the C-C bond cleavage.
Reactions of zirconacyclopentadienes with dichlorocarbene afforded cyclopropanation products in good yields. In a similar manner, reactions of zirconacyclopentadienes with a Simmons-Smith type cyclopropanation reagent also gave vinylcyclopropanes in good yields after hydrolysis. Before hydrolysis, the formation of 1-zirconabicyclo[3.1.0]hexene was observed by 13C NMR spectroscopy. The 1-zirconabicyclo[3.1.0]hexene deriatives reacted with CO to produce 1,2,3,5-tetrasubstituted benzene derivatives in good yields via the C-C bond cleavage of the cyclopropane rings. This is in sharp contrast to the formation of usual 1,2,3,4-tetrasubstituted benzene derivatives from zirconacyclopentadienes.
Takahashi
Tamotsu
T
Catalysis Research Center and Graduate School of Pharmaceutical Sciences, Hokkaido University and CREST, Science and Technology Corporation (JST), Kita-ku, Sapporo 060-0811 Japan.
Ishikawa
Masanori
M
Huo
Shoquan
S