288839-72-5

Upstream product

• 4041-77-4 ethyl 3,4-dihydroisoquinoline-1-acetate 
• 109-21-7 butyl butyrate 
• 1424-84-6 1-(ethoxycarbonylmethyl)-1,2,3,4-tetrahydroisoquinoline 
• 105-56-6 ethyl 2-cyanoacetate 
• 622-24-2 2-phenylethyl chloride 

Relevant academic research and scientific papers

Lipase-catalyzed kinetic resolution of 1,2,3,4-tetrahydroisoquinoline-1-acetic acid esters

The enantiomers of 1,2,3,4-tetrahydroisoquinoline- and 6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline-1-acetic acids were prepared via Burkholderia cepacia lipase (lipase PS-D)-catalyzed kinetic resolution of the corresponding ethyl and 2-methoxyethyl esters using enantioselective (E > 200) hydrolysis in DIPE. The (S)-acids were produced enzymatically, whereas the (R)-acids were obtained via the chemical hydrolysis of the unreacted (R)-esters. The solvent and its water content had major effects on both reactivity and enantioselectivity. The methoxyethyl moiety of the ester had a key role concerning the reactivity of the substrates.

Synthesis of simple enantiopure tetrahydro-β-carbolines and tetrahydroisoquinolines

Enantioselective hydrogenation of the imines 11-13, 27 and 30 with the Ru complex (R,R)-5 led to the tetrahydro-β-carbolines (1S)-14, (1R)-21 and (1S)-22, and the tetrahydroisoquinoline (1S)-31 with ee > 95%. By employing (S,S)-5 the enantiomers are accessible. The imines 11-12 and 27 were obtained by oxidation of racemic 14, 21 and 22 with KMnO4 in > 58% yield.