As. Golubev et al., METAL TRIFLUOROPYRUVATE IN THE PICTET-SPENGLER REACTION, Bulletin of the Russian Academy of Sciences, Division of Chemical Sciences, 41(8), 1992, pp. 1425-1429
Condensation of methyl trifluoropyruvate with 2-(3,4-dimethoxyphenyl)e
thylamine, tryptamine, and (D, L)-tryptophan yielded thyl-6,7-dimethox
y-1,2,3,4-tetrahydroisoquinoline, omethyl-1,2,3,4-tetrahydro-9H-pyrido
[3,4-b]indole, and carboxy-1,2,3,4-tetrahydro-9H-pyrido[3,4-b]indole,
respectively. The Z configuration of the latter was determined by x-ra
y structural analysis.