1356845-31-2

Upstream product

• 536-74-3 phenylacetylene 
• 1612-65-3 2-methyl-1,2,3,4-tetrahydroisoquinoline 
• 932-87-6 1-Bromo-2-phenylacetylene 
• 91-21-4 1,2,3,4-tetrahydroisoquinoline 
• 3947-78-2 2-methyl-3,4-dihydroisoquinolin-2-ium iodide 
• 114640-73-2 N-methyl-1-hydroxy-1,2,3,4-tetrahydroisoquinoleine 
• 102921-26-6 (1,2-dibromoethyl)benzene 

Relevant academic research and scientific papers

Metal-Free Activation of a C(sp)?H Bond of Aryl Acetylenes

C(sp)?H Bond activation of acetylene molecule still remains a challenge for synthetic organic chemists. In practice, acetylenes are activated by strong bases and metals. The first example for activating acetylenic protons under base and metal-free conditions is reported here. It involves a general method for synthesizing propargylic derivatives of cotarnine. An array of tetrahydroisoquinolines alkaloids was synthesized by C(sp)?H bond activation of aromatic acetylenes with cotarnine at room temperature. A DFT-based mechanism is proposed for the reaction.

Gold Catalyzed Photoredox C1-Alkynylation of N-Alkyl-1,2,3,4- tetrahydroisoquinolines by 1-Bromoalkynes with UVA LED Light

A synthetic method that combines [Au2(m-dppm)2]Cl2 (dppm=bis(diphenylphosphanyl)methane) and UVA LED (LED=light emitting diode) light (365 nm) to catalyze the regioselective C1-alkynylation of N-alkyl-1,2,3,4-tetrahydroisoquinolines (THIQs) with alkynyl bromides is described. The reaction mechanism was delineated to involve a reductive quench pathway to generate the two posited radical species of the nitrogen-containing heterocycle and organic halide. In contrast, radical formation via an oxidative quench pathway was suggested to be operative in analogous control experiments with a 1-iodoalkyne. The usefulness of this carbon-carbon bond forming strategy was also exemplified by its application to the formal synthesis of the opioid analgesic drug methopholine and synthesis of a protoberberine alkaloid derivative.

Concurrent Biocatalytic Oxidation and C-C Bond Formation via Gold Catalysis: One-Pot Alkynylation of N-Alkyl Tetrahydroisoquinolines

A cross-dehydrogenative coupling process has been developed involving the enzymatic oxidation of tetrahydroisoquinolines (THIQ) together with gold-catalyzed C-C bond-formation. The transformation demonstrates the compatibility of gold-mediated chemocatalysis and monoamine oxidase biocatalysis which act co-operatively in one vessel. A range of N-alkyl THIQs were functionalized in this manner at C-(1) position in high yields.

Improved simplicity and practicability in copper-catalyzed alkynylation of tetrahydroisoquinoline

Abstract: Alkynylation reactions of N-protected tetrahydroisoquinolines have been performed using several different protocols of cross dehydrogenative coupling. Initially, a CuCl-catalyzed method was investigated, which worked well with three different N-

C-1 alkynylation of N-methyltetrahydroisoquinolines through CDC: A direct access to phenethylisoquinoline alkaloids

Direct cross-coupling between N-methyltetrahydroisoquinolines and alkynes using CuI-DEAD is presented. It affords the regioselective C-1-alkynylated products in good yield. This regio-selectivity is in contrast to the results reported earlier in the reaction of N,N-dimethylbenzyl amine where the N-methyl alkynylated product was formed exclusively or predominantly. The C-1-substituted propargylic isoquinolines were easily reduced to phenethylisoquinolines with Pd/C. This reaction sequence provides a short route to synthesize methopholine, homolaudanosine and other phenethylisoquinoline alkaloids. Georg Thieme Verlag Stuttgart · New York.