Three-Component Domino Reaction of Thioamide, Isonitriles, and Water: Selective Synthesis of 1,2,4-Thiadiazolidin-3-ones and (E)-N-(1,2-Diamino-2-thioxoethylidene)benzamides

The three-component domino reaction of thioamides, benzyl isocyanide, and water in the presence of a catalytic amount of both Pd(dppf)Cl2 and Cu(OAc)2 afforded novel 1,2,4-thiadiazolidin-3one cyclic compounds, whereas the same reaction with tertiary alkylisonitriles in the presence of rare earth metal salt [La(OTf)3] resulted in (E)-N-(1,2-diamino-2-thioxoethylidene)benzamide open chain products. This divergent reaction enabled the one-pot construction of five (N-S, C-S, C-O, and two C-N) or four (C- S, C-N, C-O, and C-C) new chemical bonds. Mechanism studies indicate that the oxygen atom of the product was derived from H2O.

Automated summary

Under the catalysis of both Pd(dppf)Cl2 and Cu(OAc)2, a three-component domino reaction of thioamides, benzyl isocyanide, and water resulted in novel 1,2,4-thiadiazolidin-3-one cyclic compounds. In contrast, the same reaction with tertiary alkylisonitriles in the presence of rare earth metal salt [La(OTf)3] produced (E)-N-(1,2-diamino-2-thioxoethylidene)benzamide open chain products. This divergent reaction enabled the formation of five (N-S, C-S, C-O, and two C-N) or four (C-S, C-N, C-O, and C-C) new chemical bonds. Mechanism studies revealed that the oxygen atom in the product was derived from water.