Aromatic nucleophilic substitution on h6-Cr(CO)3-complexed haloarenes. Arylation of secondary carbanions

Nucleophilic arom. substitution of fluorobenzene- or dichlorobenzene(tricarbonyl)chromium complexes with carbanions from CH2RR1 (R = Ph, CO2Et, R1 = CN; R = R1 = CO2Et) under phase-transfer conditions or in DMSO soln., followed by decomplexation with iodine, gave substituted benzenes R3C6H4CHRR1 (R, R1 = same, R2 = H, 2-, 3-, and 4-Cl). Addn. of BuSH before decomplexation in the dichlorobenzene reactions gave 2- or 4-BuSC6H4CH(CN)CO2