PtI2(PPh3)2 catalyzes hydrosilylation of 2,2-diphenyl-1-methylenecyclopropane with HSiEt3, HSiPh3, HSiEt2Ph, HSiPhCl2, and HSiCl3 under solvent-free conditions at 140°C to produce the silyl compounds with a (2,2-diphenylcyclopropyl)methyl substituent in moderate to high yields without ring-opening of the substrate. PtI2(PPh3)2 is converted by the reaction into PtH(I)(PPh3)2, which also catalyzes the hydrosilylation of the methylenecyclopropanes. The reaction of 2-phenyl-1-methylenecyclopropane, 2-methyl-2-phenyl-1-methylenecyclopropane, 2,2-diphenethyl-1-methyl-enecyclopropane, and alkylidenecyclopropanes with HSiEt3 catalyzed by PtI2(PPh3)2 causes addition of hydrosilane to the substrate accompanied by ring-opening. 2,2-Diphenyl-1-methylenecyclopropane undergoes ring-opening isomerization in the presence of HSi(OEt)Me2 and Pt(PEt3)3 catalyst to give 1,1-diphenyl-1,3-butadiene. The pathways for the hydrosilylation and the isomerization are discussed.
ASJC Scopus subject areas
- Organic Chemistry