A series of benzylidene-3-pyrrolines were prepared from chalcone derivatives,\narylacetylene and sulfonamide via a three-step sequence without the isolation of intermediates.\nTypically, the reaction of 1,3-di-p-tolylprop-2-en-1-one with lithium phenylacetylide was\nfollowed by substitution with tosylamide and then silver-catalyzed 5-exo-dig cyclization to\ngive N-tosyl-2-benzylidene-3,5-di-p-tolyl-2,5-dihydro-1H-pyrrole with a 86% yield. Furthermore,\ntransformation to the corresponding substituted 3-pyrrolin-2-one and pyrrole by m-chloroperbenzoic\nacid (mcpba)-oxidation and acid-catalyzed aromatization, respectively, was investigated.
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