Synthesis of quinoxaline 1,4-dioxides from benzofuroxan proceeds not in, but on zeolite

Quinoxaline synthesis using Na-zeolite A as a catalyst to proceeds in a better yield than that using zeolite X. The pore diameter of zeolite X is large enough to allow the benzofuroxan derivatives access to cages, therefore part of benzofuroxan is adsorbed in the internal surface of zeolite X. Whereas the windows to the cages of Na-zeolite A are too small to allow the benzofuroxan derivatives access to the cages, therefore all the benzofuroxan is adsorbed on the external surface of zeolite. The reactions of benzofuroxans with benzoylacetone was catalyzed by zeolite proceed not in, but on zeolite.