124687-77-0

Upstream product

• 120-20-7 2-(3,4-dimethoxyphenyl)-ethylamine 
• 99930-84-4 Trimethyl-((S)-toluene-4-sulfinylethynyl)-silane 
• 99930-83-3 (R)-ethynyl-p-tolyl-sulfoxide 
• 1517-82-4 (-)-menthyl p-toluenesulfinate 
• 3382-18-1 6,7-dimethoxy-3,4-dihydro-isoquinoline 
• 112572-16-4 lithium (R_S)-(+)-methyl p-tolyl sulfoxide 
• 1519-39-7 (R)-methyl p-tolyl sulfoxide 

Downstream Products

• 124687-79-2 (1S,R_S)-N-<(2,3-dimethoxyphenyl)methyl>-3,4-dihydro-6,7-dimethoxy-1-<(p-tolylsulfinyl)methyl>isoquinoline 
• 3520-14-7 (R)-(+)-tetrahydropalmatine 
• 124687-80-5 (+)-(13S,13aS)-5,8,13,13a-tetrahydro-2,3,9,10-tetramethoxy-13-<(4-methylphenyl)thio>-6H-dibenzoquinolizine 

Relevant academic research and scientific papers

Chiral Acetylenic Sulfoxide in Enantioselective Synthesis of Tetrahydroisoquinoline and Tetrahydro-β-carboline Alkaloids. Total Synthesis of (R)-(+)-Carnegine and (R)-(+)-Tetrahydroharman

Michael addition of 2-(3,4-dimethoxyphenyl)ethylamine 3 or tryptamine 4 onto chiral acetylenic sulfoxides 2 followed by acid induced cyclization afforded the basic alkaloid skeleton of tetraisoquinoline and tetrahydro-β-carboline in high to moderate diastereoselectivity.Optically pure (R)-(+)-carnegine and (R)-(+)-tetrahydroharman have been synthesized.

Chiral acetylenic sulfoxide in alkaloid synthesis. Total synthesis of (R)-(+)-carnegine

Remarkable diastereoselectivity was observed in the cyclization of β-aminovinyl sulfoxide 5a prepared from chiral acetylenic sulfoxide 1a in acidic medium. The cyclized product 6a was then converted to (R)-(+)-carnegine.

Diastereoselective Additions of (R)-(+)-Methyl p-Tolyl Sulfoxide Anion to Imines. Asymmetric Synthesis of (R)-(+)-Tetrahydropalmatine

The addition of the lithium carbanion of methyl phenyl sulfoxide and (R)-(+)-methyl p-tolyl sulfoxide to imines having at least one aryl substituent, under kinetically controlled conditions, gives β-amino sulfoxides with good to modest diastereoselection.Under equilibrium controlled condition poor product diastereoselection results.The addition of these anions to 3,4-dihydro-6,7-dimethoxyisoquinoline is unique in that the most favorable product diastereoselection (92:8) is observed under equilibrium controlled conditions.Deuteration experiments suggest that equilibration occurs via a β-amino α-lithio sulfinyl carbanion through a retro-Michael addition then Michael addition reaction sequence.This methodology allows for the construction of (R)-(+)-tetrahydropalmatine in four efficient synthetic steps.

Diastereoselective Kinetically and Thermodynamically Controlled Additions of (R)-(+)-Methyl p-Tolyl Sulphoxide Anion to Imines (Tolyl = C6H4Me)

The anion of (R)-(+)-methyl p-tolyl sulphoxide reacts diastereoselectively with imines to give chiral β-amino sulphoxides.