| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1345175 | Tetrahedron: Asymmetry | 2007 | 5 Pages |
The protoberberine-type alkaloid, (S)-(−)-O-methylbharatamine, has been synthesized in six steps involving the addition of laterally lithiated o-toluamide to (S)-N-tert-butanesulfinimine as the crucial process. The target alkaloid was obtained in 24.4% overall yield with 88% ee.
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(S)-(+)-N-(3,4-Dimethoxybenzylidene)-2-methylpropanesulfinamideC13H19NO3S[α]D = +19.8 (c 0.57, CH2Cl2)Source of chirality: (S)-tert-butanesulfinamideAbsolute configuration: (S)
(S,S)-(−)-N-[1-(3,4-Dimethoxyphenyl)-2-(2-N,N-diethylbenzamide)ethyl]-2-methylpropanesulfinamideC25H36N2O4S[α]D = −18.3 (c 0.95, MeOH)Source of chirality: (S)-tert-butanesulfinamideAbsolute configuration: (S,S)
(S)-(+)-N,N-Diethyl-2-[2-amino-2-(3,4-dimethoxyphenyl)ethyl]benzamide hydrochlorideC21H29ClN2O3[α]D = +36.6 (c 1.14, EtOH)Source of chirality: (S)-tert-butanesulfinamideAbsolute configuration: (S)
(S)-(−)-3-(3,4-Dimethoxyphenyl)-1,2,3,4-tetrahydroisoquinoloneC17H17NO3Ee = 72%[α]D = −76.2 (c 0.28, MeOH)Source of chirality: (S)-tert-butanesulfinamideAbsolute configuration: (S)
(S)-(−)-3-(3,4-Dimethoxyphenyl)-1,2,3,4-tetrahydroisoquinolineC17H19NO2[α]D = −83.0 (c 1.17, CH2Cl2)Source of chirality: (S)-tert-butanesulfinamideAbsolute configuration: (S)
