Studies On The Transition-Metals Catalyzed Carbon-Heteroatom Bond Formation Reactions In Ionic Liquids

This paper consists of three parts:Part 1:We investigated the palladium-catalyzed hydroalkoxylation reaction of homoallylic alcohols with methanol with a migration of double bond in ambient temperature ionic liquid [Bmim][PF₆], it was found that the hydroalkoxylation reaction could proceed smoothly at 30℃to afford stereoselectively the corresponding (E)-allylic ethers in high yields. Compared to the same reaction run in toluene or methanol, the [Bmim][PF₆] and palladium catalyst can be recycled many times without noticeable decrease in yields. This methodology has provided a green method for the synthesis of (E)-allylic ethers.Part 2: We investigated RuCl₃-catalyzed the condensation reaction of aldehydes and ketones with thiols in the mixture of ionic liquid and CH₃CN. The results showed that RuCl3 has high catalytic activity and ionic liquid and ruthenium catalyst can recycle many times without noticeable decrease in yields. This methodology has provided a green method for the synthesis of thioacetals.Part 3: We investigated the palladium-catalyzed hydrostannylation of alkynes for the stereoselective synthesis of disubstituted vinylstannanes, it was found that the hydrostannylation reaction could proceed smoothly at 25℃to afford stereoselectively the corresponding (E)-disubstituted vinylstannanes in high yields. Compared to the same reaction run in THF, diethyl ether and toluene, the [Bmim][PF₆] and palladium catalyst can be recycled many times without noticeable decrease in yields. This methodology has provided a green method for the synthesis of (E)- disubstituted vinylstannanes..