The first example of hydrozirconation of alkynes in room temperature ionic liquids
摘要:
Hydrozirconation of terminal alkynes in 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim] [PF6]) at 30 degrees C gave highly regio-and stereoselectively (E)-vinylzirconium complexes, which underwent a cross-coupling reaction with aryl halides in the presence of Pd(PPh3)(4) to afford (E)-1,2-disubstituted ethenes in good to high yields. Our system not only avoids the use of easily volatile THF or CH2Cl2 as solvent but also solves the basic problem of palladium catalyst reuse. (C) 2011 Elsevier B. V. All rights reserved.