Copper-Catalyzed C-N Bond Cleavage: Synthesis of N-Sulfonylformamidines from N-( 2-pyridinylmethyl)benzenesulfonamides

AIMS

Find an innovative approach to synthesizing N-sulfonylformamidines from new N source.

BACKGROUND

N-sulfonylamidines have gained considerable attention from school and industry because of unique bioactivity. Since Pinner's strategy, expanding the synthesis methods of N-sulfonylamidines has been the goal of many organic chemists over the past decades. Beside of the crash reaction conditions and the participation of undesirable reagents, the production of N-sulfonylamidines commonly required unstable ammonia and azides as the source of nitrogen which hindered the further development and application of N-sulfonylamidine derivatives.

OBJECTIVE

Find a stable N source to replace NaN3 or NH3 to synthesis N-sulfonylamidines.

METHOD

Firstly, N-( 2-pyridinylmethyl)benzenesulfonamides were smoothly synthesized via 2-pyridinemethanamine and sulfonyl chlorides. Then the reaction conditions of N-(2-pyridinylmethyl)benzenesulfonamides and N,N-dimethylformamide dimethyl acetal(DMF-DMA) were screened and optimized: the reaction was processed in glycol at 80 ℃ for 8 hours with the addition of 5 mol% Cu(OAc)2·H2O as catalyst.

RESULT

Taking the advantage of pyridin-2-ylmethyl, a scope of N-Sulfonylformamidines were synthesized from those N-(2-pyridinylmethyl)benzenesulfonamides under copper-catalyzed C-N bond cleavage.

CONCLUSION

This ready synthetic method will be more a promising inspiration of bioactive compound synthesis and drug development than of an innovative approach to synthesizing N-sulfonylformamidines.

Interception of amide ylides with sulfonamides: synthesis of (E)-N-sulfonyl amidines catalyzed by Zn(OTf)2

Through the interception of amide ylides with sulfonamides, we herein report an intermolecular condensation reaction between sulfonamides and common amides.