Isoquinolones tetrahydro

A novel route to ( )-0-methylthalisopavine (26) involves the oxidation of the properly substituted tetrahydro-3-isoquinolone of type 129 with vanadium oxy-trifluoride to furnish bridged lactam 130. Compound 130 was then reduced to the racemic isopavine alkaloid 26 in an overall yield of 4.4% (Scheme 26) 136). 

Isochroman-3-ones on reaction with HBr/EtOH furnish the bromoesters which on treatment with amines provide isoquinolones. The latter on reduction with LiAlH give 1,2,3,4-tetrahydro isoquinolines... 

Ring expansion. A mixture of 2-benzyl-l,2-dihydro-7-methoxy-4(3H)-isoquinolone oxime, LiAlH4, and dry tetrahydrofuran stirred and refluxed 6 hrs. 4-benzyl-7-methoxy-l,3,4,5-tetrahydro-2H-l,4-benzodiazepine. Y 35%. R. I. Fryer et al., J. Org. Chem. 35, 2455 (1970). 

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