A general procedure for the synthesis of methylthio-, methylseleno- and methyltelluro-substituted aromatic compounds
作者:Lars Engman、Jonas S.E. Hellberg
DOI:10.1016/0022-328x(85)80366-1
日期:1985.12
A one-pot procedure is described which allows the facile introduction of one or two methylchalcogeno groups into a variety of monobromo or dibromo aromatics. The bromo compounds were converted to their corresponding lithio derivatives by treatment with t-butyllithium in tetrahydrofuran at −78°C, and these derivatives were then treated, at ambient temperature with elemental sulfur, selenium, or tellurium
trifluoroacetic anhydride followed by quenching with aqueous NaHCO3 gives 9,9-bis(methylthio)-10-anthraquinone. The dithia dication and/or the corresponding carbodication via through-bondinteraction between sulfonium and sulfenyl sulfur atoms is proposed as an intermediate.