Nitrones and Oxaziridines. XLV. Formation of Pyrroloindoles by Intramolecular Nitrone Cycloaddition

Article abstract of DOI:10.1071/CH9930603

The N-allylindole-2-carbaldehydes (5)-(8) and related methyl ketones (9)-(12) undergo reaction with N-methylhydroxylamine to give the cycloadducts (14)-(17) and (19)-(22), respectively.These adducts contain isoxazolidine rings fused to pyrrolo<1,2-a>indole systems.Corresponding cycloaddition of the N-propargylindole derivatives (24) and (25) could not be effected and the nitrone (26) was isolated.The adducts (14)-(17) underwent hydrogenolysis of the isoxazolidine N-O bond to give the amino alcohols (27)-(30), together with traces of the alcohols (31)-(34).X-Ray crystallographic data for the cycloadducts (15) and (16b) are presented.