The thionophosphate-thiolophosphate photoisomerization proceeds predominantly through a non-chain radical pathway. Synthetically viable benzylation of tetrahydrofuran, propan-2-ol and olefins

Abstract

The photoirradiation of thionophosphates, ROP(S)(OEt)₂, derived from benzyl and vinylogously benzyl alcohols in CH₃CN, with a Hanovia medium-pressure mercury lamp in a quartz vessel leads to the formation of the corresponding thiolophosphates, RSP(O)(OEt)₂, through a non-chain radical pathway. This behavior of thionophosphates is unlike that of the related phosphates, which react through ionic dissociation-recombination processes. When the irradiation is conducted in solvents such as PrⁱOH, THF and toluene, benzylation of these solvents takes place in synthetically respectable yields. Irradiation of thionophosphates in CH₃CN leads to a convenient allylic benzylation of olefins.