Rhodium Catalysts Cleave Cyclobutanol to Asymmetric Methyl Quaternary Centers

Significance

Chiral rhodium(I) phosphine complexes are utilized to the cleavage of cyclobutanol substrates. One of the two bonds proximal to the hydroxyl in the cyclobutane ring was cleaved selectively to generate an alkylrhodium(I) species which undergoes protonation to provide the highly enantioenriched desired products. An example of highly enantioselective synthesis of the simplest chiral hydrocarbon, 4-ethyl-4-methyl-octane, was shown to demonstrate the utility of this reaction.