Influence of conditions and N-substituent on the reactions of 6-methoxy-3-methyl-6,6a-dihydrofuro[3,4-d]isoxazol-4-one with hydrazines

The reactions of the title compound with hydrazines are studied to shed lig ht on the course of the reaction of gamma -alkoxyfuran-2(5H)-ones with thes e binucleophiles. At room temperature, both unsubstituted hydrazine and phe nylhydrazine in ethanol, or hydrazine and its methylderivative in ethanol-a cetic acid, afforded good yields of 5-amino-, 5-phenylamino-, and 5-methyla mino-6-hydroxy-3-methyl-3a,5,6,6a-tetrahydro-4H-pyrrolo[3,4-d]isoxazol-4-on es. Only the methylhydrazine, in ethanol at room temperature, gave a deriva tive of the isoxazolo[4,5-d]pyridazin-4(3aH)-one system. No pyridazinone de rivative is obtained from phenylhydrazine. (C) 2001 Elsevier Science Ltd. A ll rights reserved.