Synthesis of 1,3-Disubstituted N-Amino-1,2,3,4-tetrahydroisoquinolines.

1
2007 Isoquinoline derivatives R 0420 Synthesis of 1,3-Disubstituted N-Amino-1,2,3,4-tetrahydroisoquinolines. — The title isoquinolines are prepared from aldehydes and 2-arylethyl hydrazides via the Pictet—Sprengler reaction. The effects of substituents at the phenyl group of the hy- drazide and the type of aldehyde are studied. The electron-donating methoxy group is very important for a successful reaction and works only in the meta-position to the hydrazide moiety. An additional methoxy group in the para-position is useful. The type of aldehyde greatly influences the diastereoselectivity of the reaction. Excellent trans-selectivities are achieved for p-bromo- and p-nitrobenzaldehyde. — (ZHANG, L.; ZHENG, X.-F.; LINN, G.; ZHAO*, K.; Synlett 2007, 3, 374-380; Sch. Pharm. Sci. Technol., Tianjin Univ., Tianjin 300072, Peop. Rep. China; Eng.) — Klein 25- 141

Transcript of Synthesis of 1,3-Disubstituted N-Amino-1,2,3,4-tetrahydroisoquinolines.

Page 1: Synthesis of 1,3-Disubstituted N-Amino-1,2,3,4-tetrahydroisoquinolines.

2007

Isoquinoline derivativesR 0420 Synthesis of 1,3-Disubstituted N-Amino-1,2,3,4-tetrahydroisoquinolines. — The

title isoquinolines are prepared from aldehydes and 2-arylethyl hydrazides via the Pictet—Sprengler reaction. The effects of substituents at the phenyl group of the hy-drazide and the type of aldehyde are studied. The electron-donating methoxy group is very important for a successful reaction and works only in the meta-position to the hydrazide moiety. An additional methoxy group in the para-position is useful. The type of aldehyde greatly influences the diastereoselectivity of the reaction. Excellent trans-selectivities are achieved for p-bromo- and p-nitrobenzaldehyde. — (ZHANG, L.; ZHENG, X.-F.; LINN, G.; ZHAO*, K.; Synlett 2007, 3, 374-380; Sch. Pharm. Sci. Technol., Tianjin Univ., Tianjin 300072, Peop. Rep. China; Eng.) — Klein

25- 141