A multicomponent reductive cross-coupling of unactivated alkyl halides and alkyl tosylates connected via sodium metabisulfite was established for the general construction of alkyl–alkyl sulfones. Neither a metal catalyst nor a metal reductant is required in this “green” reductive cross-coupling. Inorganic sodium metabisulfite served as both the sulfur dioxide source and the robust connector. Safe formate was used as a highly efficient single-electron reductant. Both intramolecular and intermolecular reductive cross-couplings were achieved with broad substrate scopes. Diverse biologically important molecules were efficiently cross-linked with steroids, saccharides, amino acids, peptides, and pharmaceuticals with sensitive functional groups, affording sulfone-bridged hybrid molecules. Mechanistic studies demonstrated that alkyl radicals were involved in the singly occupied molecular orbital (SOMO) of the metabisulfite salt, initiating the transformation.

建立了未活化的烷基卤化物和烷基甲苯磺酸盐通过偏亚硫酸氢钠连接的多组分还原交叉偶联反应，用于烷基烷基砜的一般结构。在这种“绿色”还原交叉偶联中，既不需要金属催化剂也不需要金属还原剂。无机焦亚硫酸钠既可以作为二氧化硫源，也可以作为坚固的连接器。安全甲酸盐被用作高效的单电子还原剂。分子内和分子间还原性交叉偶联均在较宽的底物范围内实现。多种生物学上重要的分子可与类固醇，糖，氨基酸，肽和具有敏感官能团的药物有效地交联，从而提供砜桥杂化分子。