| Abstract
| - Enamides 5, on treatment with Bu3SnH−AIBN, underwent aryl radical cyclization in a 5-exo mannerto give 1-[bis(phenylthio)methyl]dihydroisoindoles 6, which were partially desulfurized withBu3SnH−AIBN to give 1-mono(phenylthio)methyl congeners 7. Formation of 6 from 5 may beexplained by the presence of two phenylthio groups at the terminus of the N-vinylic bond of 5,since enamide 8a having no phenylthio group underwent aryl radical cyclization in a 6-endo manner.Compound 7d (R = CF3) was transformed into sulfoxide 16, which was treated with (CF3CO)2Oand then with 10% NaOH to give a model compound 20 of mappicine ketone (MPK) (1) throughaldol condensation of aldehyde 18. An attempt to synthesize MPK using this method with sulfoxide28 prepared from 25, however, was unsuccessful, and, instead, photochemical cyclization of enamide38 prepared from 25 furnished MPK.
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