75349-97-2Relevant academic research and scientific papers
Reactions of Cyclopropenes, IV. Cyclooligomerisation of 3,3-Dimethylcyclopropene with Palladium(0) Catalysts
Binger, Paul,McMeeking, John,Schuchardt, Ulf
, p. 2372 - 2382 (2007/10/02)
The cyclooligomerisation of 3,3-dimethylcyclopropene (1) with phosphane-free palladium(0) catalysts, e.g. bis(1,5-cyclooctadiene)palladium, bis(dibenzylideneacetone)palladium, or a catalyst prepared "in situ" from palladium acetylacetonate and ethoxydiethylaluminium, leads to the trans-tricyclohexane derivative 2 and to three isomeric tetrakishomocyclooctatetraene compounds (4) .In contrast, a (tri-sec-alkylphosphane)palladium(0) catalyst (Pd/P = 1:1) cyclotrimerises 1 in aromatic hydrocarbons to give the trans-?-trishomobenzene derivative 3 in over 90percent yield.The cyclooligomerisation of 1 using other triorgano-phosphane or -phosphite/palladium(0) catalysts leads to a mixture of products.Besides 2, 3, and 4 a second cyclotrimer of 1 (5) and higher oligomers of 1 are produced.The cyclotrimerisation of 1 to 3 is also influenced by the Pd/phosphane ratio and the solvent used.
