Abstract
Alkoxy-substituted 2-aklyl-1,3,4(2H)-isoquinolinetriones (7) react with trialkyl phosphites to give the corresponding 1,3(2H,4H)-isoquinolinedion-4-ylidene derivatives 8 and trialkyl phosphates. The reaction of 8 with trialkyl phosphites in the presence of water affords reduction products shown to be 1,3(2H,4H)-isoquinolinedion-4-yl derivatives 9 by the spectral data and X-ray crystallography.