J. Kiji, T. Okano, H. Kimura
Mar 12, 1998
Citations
0
Influential Citations
13
Citations
Journal
Journal of Molecular Catalysis A-chemical
Abstract
Abstract Carbonylative coupling of iodobenzene and 2-methyl-3-butyn-2-ol ( 4 ) in aqueous NaOH/benzene was carried out by using Pd(OAc) 2 /Ph 3 P/Bu 4 PBr ( A ) and Pd(OAc) 2 /Ph 2 P(m-C 6 H 4 SO 3 Na) ( B ) as catalyst. In sharp contrast with a homogeneous Et 3 N solution, this biphasic solvent system gives 3-isopropylidene-5-phenyl-2(2H)-furanone ( 1 ) in a moderate yield. The other carbonylated products are 2,2-dimethyl-5-phenyl-3(2H)-furanone ( 2 ) and benzoic acid. The formation of 1 is explained by the following sequential reactions; carbonylative coupling of iodobenzene with 4 to form 4-hydroxy-4-methyl-1-phenyl-2-pentyn-1-one ( 6 ), hydrogenolysis of 6 to 4-methyl-1-phenyl-2,3-pentadien-1-one ( 8 ) and its cyclocarbonylation to 1 . Catalyst A gives 1 in a higher yield than B .