Condensation Reactions of Sulfonylcarbanion

Phenylsulfonylcarbanion PhSO2CH2− reacts with anthracene and acridine in HMPA to afford methylated products much as does methylsulfinylcarbanion MeSOCH2− in DMSO. The reaction mechanism is examined by following the change in the D-content during the reaction of 9-deuterioanthracene. The transformation of the negatively-charged σ-complex into the methylated product involves the concerted occurrence of a hydride shift and the elimination of the sulfinate anion. Meanwhile, the reaction of this carbanion with anthracene at a higher temperature yields the ethylated products of 9-ethyl-10-methyl- and 9,10-diethylanthracene besides 9,10-dimethylanthracene. Other condensation reactions of the carbanion investigated are those with (a) Ph2C=CH2, (b) PhC≡Cph, (c) Ph2CO, (d) PhCOCOPh, and (e) 2-aminobenzophenone, the main products being (a) (Remark: Graphics omitted.), (b) Ph2C=C(Ph)Me, (c) Ph2C(OH)CH2CH2SO2Ph and Ph2C=CHCH2SO2Ph, (d) PhCOCH2SO2Ph and PhCOOH, and (e) 3-phenylindole respectively.