Intramolecular dearomative 1,4-addition of silyl and germyl radicals to a phenyl moiety.

Herein, we present that the radicals [Ph 3 PC(Me)EMes 2 ]˙ (2Si and 2Ge) can be generated from the α-silylated and α-germylated phosphorus ylides Ph 3 PC(Me)E(Cl)Mes 2 (1Si and 1Ge) through one-electron reduction with Jones' dimer ( Mes NacNacMg) 2 in benzene. Although isolation of the free radicals was not possible, the products of the intramolecular addition of the radicals to a phenyl substituent of the phosphorus moiety, followed by subsequent reaction with 2Si or 2Ge to the isolated species 3Si and 3Ge, respectively, were observed. This transformation witnesses a dearomative 1,4-addition of tetryl radical species to the phenyl scaffold in a stereoselective anti -fashion.