Methylene-cyclopentane derivs. prodn. - by co:dimerisation of methylene-cyclopropane with olefin cpds. in the presence of palladium complexes

摘要

In a new process for the prodn. of methyl-cyclopentanes substd. by catalytic codimerisation of methylene-cyclopropane with olefins, the codimerisation is carried out in the presence of Pd(O) cpds. as catalysts. Of the prod., the following are claimed as new cpds. The prods. are of interest as intermediates for natural prods. e.g. prostaglandins. Cycloadditions prods. of methyl-cyclopropane with cyclic allenes can be subjected to ring-enlargement reactions, e.g. 1,2-cyclodecadiene can be used for a muscone synthesis. In an example, methylene-cyclopropane in benzene is reacted with ethylene at 120 atm. in the presence of Pd acetylacetonate, triisopropylphosphane and diethyloxyaluminium to give methylenecyclopentane and 5-methylenespiro 4.2 heptane.