Biomimetic Construction of the Hydroquinoline Ring System. Diastereodivergent Enantioselective Synthesis of 2,5-Disubstituted <i>cis</i>-Decahydroquinolines
The straightforward enantioselective construction of the hydroquinoline ringsystemfrom 1,5-polycarbonyl derivatives, using (R)-phenyglycinol as a chiral latent form of ammonia, is reported. The process mimics the key steps believed to occur in nature in the biosynthesis of amphibian decahydroquinoline alkaloids. Diastereodivergent routes to enantiopure cis-2,5-disubstituted decahydroquinolines, including
The earlier structural assignment as 2 for the dione obtained by the base treatment of 1a or 1b is confirmed. Syntheses of substituted 1,2-benzocyclooct-1-en-6-ones are reported.