F. Fulop et al., SATURATED HETEROCYCLES .252. SYNTHESIS AND STEREOCHEMISTRY OF STEREOISOMERIC 6-METHYL-SUBSTITUTED PYRIMIDO[6,1-ALPHA]ISOQUINOLINES, Liebigs Annalen, (6), 1997, pp. 1165-1171
Stereoisomeric (1R,3R*)- and methyl-1,2,3,4-tetrahydroisoquinoline-1-
acetamides 5-8 react with formaldehyde or benzaldehyde to furnish ster
eoisomeric pyrimido[6,1-a]isoquinolin-2-ones 9-18. the relative config
urations and the predominant conformations of the products have been d
etermined by NMR spectroscopy, and for ,6,7,11b-hexahydropyrimido[6,1-
a]isoquinolin-2-one (11) by X-ray diffraction.