2,2-Diethoxyacetaldehyde → 8-Bromoisoquinolin-1(2H)-one

Participants

Reaction Steps

The isoquinolin-8-yl system can be prepared from the appropriately substituted benzylamine by cyclocondensation with diethoxy-acetaldehyde (see, for example, K. Kido and Y. Watanabe, Chemical & Pharmaceutical Bulletin, 35(12), 4964-6; 1987). Alternatively 8-bromo-isoquinoline (prepared by the method of F. T. Tyson, J.A.C.S., 1939, 61, N. Briet et al., Tetrahedron (2002), 58(29), 5761-5766 or W. D. Brown, et al., Synthesis (2002), (1), 83-86. 183 can be subjected to N-oxidation and rearrangement to give 8-bromo-2H-isoquinolin-1-one. This can be N-methylated to give 8-bromo-2-methyl-2H-isoquinolin-1-one, an appropriate intermediate for the 2-methyl-1-oxo-1,2-dihydroisoquinolin-8-yl system.

Provenance & Evidence