REACTIONS OF α-CHLOROIMINES WITH HOMOPHTHALIC ANHYDRIDES. SYNTHESIS AND MOLECULAR STRUCTURE OF 3,3a-DIHYDROFUROISOQUINOLINE-1,5(4H,9bH)-DIONES, FURO-8,9,16,16a-TETRAHYDRO-1H,3H,11H-DIBENZOQUINOLIZINE-1,11-DIONES AND RELATED COMPOUNDS

Article abstract of DOI:10.1016/S0040-4020(01)86402-4

The reaction of α-chloroimines 1-3, resp. 11 with homophthalic anhydrides 4 leads to the formation of the isoquinoline ring system incorporated in furo<3,4-c>isoquinolinediones 8-10, resp. 13a-(chloromethyl)-8H-dibenzo-quinolizine-8-one-13-carboxylic acids 12.The latter compounds were converted into furo<3',4':9,9a>dibenzoquinolizinediones 13 under basic conditions.NMR studies provided information concerning the relative configuration and the solution conformation of the various heterocycles obtained.The molecular structure of 8b and 12b was determined by X-ray analysis.