The Formation of an Enantiomerically Pure Product of Free Radical Coupling. The Chemistry of Diphenylcarbene in Polycrystalline (S)-(+)-2-Butanol

Article abstract of DOI:10.1021/ja00310a050

Photolysis of 0.1 M diphenyldiazomethane at 77 K or 137 K in solid (S)-(+)-2-butanol gives tertiary alcohol 9 along with other products.Compound 9 was isolated and found to be enantiomerically pure by chiral NMR shift reagents.Compound 9 is formed by reaction of triplet diphenylcarbene with (S)-(+)-2-butanol to give a radical pair which subsequently collapses.The solid-state matrix directs the radical pair collapse with complete retention of configuration.