135365-22-9Relevant academic research and scientific papers
Asymmetric hydrogenation kinetic resolution method of racemic polysubstituted dihydroisoquinoline
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Paragraph 0115-0120, (2021/11/26)
The invention relates to the field of asymmetric catalytic hydrogenation, in particular to an asymmetric hydrogenation kinetic resolution method of racemic polysubstituted dihydroisoquinoline. The method comprises the steps of in the presence of a chiral diamine metal catalyst, performing asymmetric hydrogenation treatment on a mixture containing enantiomers of the polysubstituted dihydroisoquinoline compound by adopting hydrogen to obtain single optical isomers of the polysubstituted chiral tetrahydroisoquinoline compound and the polysubstituted chiral dihydroisoquinoline compound, wherein the polysubstituted dihydroisoquinoline compound is a compound as shown in a formula (1) in the description; and the polysubstituted chiral tetrahydroisoquinoline compound is a compound as shown in a formula (2) in the description. According to the method disclosed by the invention, resolution of the racemic polysubstituted dihydroisoquinoline compound is realized in an asymmetric hydrogenation manner, and a polysubstituted chiral tetrahydroisoquinoline compound with certain optical purity and a single optical isomer of the polysubstituted chiral dihydroisoquinoline compound with certain optical purity can be obtained at the same time.
A Modified Bischler-Napieralski Procedure for the Synthesis of 3-Aryl-3,4-dihydroisoquinolines
Larsen, Robert D.,Reamer, Robert A.,Corley, Edward G.,Davis, Paul,Grabowski, Edward J. J.,et al.
, p. 6034 - 6038 (2007/10/02)
A modification of the Bischler-Napieralski reaction for the cyclization of (1,2-diphenylethyl)amides to the 3-aryl-3,4-dihydroisoquinolines is presented.Elimination of the amide group as the nitrile via the retro-Ritter reaction is avoided by its conversion to an N-acyliminium intermediate with oxalyl chloride-FeCl3.Removal of the oxalyl group in refluxing MeOH-sulfuric acid provides the 3,4-dihydroisoquinolines in moderate to high yields.The method is also highly effective with (2-phenylethyl)amides.
