33770-41-1

Upstream product

• 120-20-7 2-(3,4-dimethoxyphenyl)-ethylamine 
• 3535-37-3 3,4-dimethoxybenzoic acid chloride 
• 102011-15-4 N-<2-(3,4-dimethoxyphenyl)ethyl>-3,4-dimethoxyphenylacetamide 
• 15547-57-6 1-(3,4-dimethoxy-phenyl)-6,7-dimethoxy-3,4-dihydro-isoquinoline 

Downstream Products

• 15547-57-6 1-(3,4-dimethoxy-phenyl)-6,7-dimethoxy-3,4-dihydro-isoquinoline 
• 33770-43-3 (S)-1-1-(3',4'-dimethoxylphenyl)-1,2,3,4-tetrahydro-6,7-dimethoxyisoquinoline 
• 15547-55-4 1-(3',4'-dimethoxyphenyl)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline 

Relevant academic research and scientific papers

Asymmetric transfer hydrogenation of imines in water/methanol co-solvent system and mechanistic investigation by DFT study

Asymmetric transfer hydrogenation of various cyclic imines proceeded efficiently with water/methanol co-solvent media in 20 min with excellent yields and enantioselectivities by employing Rh-TsDPEN catalyst and sodium formate as a hydrogen donor. The role

Asymmetric synthesis of 1-substituted tetrahydroisoquinolines by nucleophilic addition to hydrazonium ions. Application to the enantioselective syntheses of (+)- and (-)-salsolidines and (-)-cryptostyline II

Nucleophilic addition of carbon nucleophiles and metal hydride reagents to hydrazonium salts modified by optically active 2-substituted pyrrolidine auxiliaries leads to highly enantioselective synthesis of 1-substituted tetrahydroisoquinolines. This methodology was applied to asymmetric synthesis of the title isoquinoline alkaloids.

Enantioselective Synthesis of 1-Aryl-Substituted Tetrahydroisoquinolines Through Ru-Catalyzed Asymmetric Transfer Hydrogenation

A convenient and general asymmetric transfer hydrogenation of a wide array of 1-aryl-3,4-dihydroisoquinoline derivatives using a [RuIICl(η6-benzene)TsDPEN] complex in combination with a 5:2 HCOOH-Et3N azeotropic mixture as a hydrogen source was developed. Under mild reaction conditions, the described catalytic transformation secured a practical synthetic access to the corresponding valuable chiral 1-aryltetrahydroisoquinoline units with high atom economy, a broad substrate scope, high isolated yields (up to 97%) and good to excellent enantioselectivities (up to 99% ee). It was found that the stereochemical outcome of the reaction was strongly influenced by both the structure of the catalyst and the substituents present on the substrate. The synthetic utility of the present protocol has been demonstrated through the asymmetric synthesis of several biologically important alkaloids including the antiepileptic drug agent 1c, as well as (-)-nor-cryptostyline alkaloids I and II.

Asymmetric Transfer Hydrogenation of Imines in Water by Varying the Ratio of Formic Acid to Triethylamine

Asymmetric transfer hydrogenation (ATH) of imines has been performed with variation in formic acid (F) and triethylamine (T) molar ratios in water. The F/T ratio is shown to affect both the reduction rate and enantioselectivity, with the optimum ratio being 1.1 in the ATH of imines with the Rh-(1S,2S)-TsDPEN catalyst. Use of methanol as a cosolvent enhanced reduction activity. A variety of imine substrates have been reduced, affording high yields (94-98%) and good to excellent enantioselectivities (89-98%). In comparison with the common azeotropic F-T system, the reduction with 1.1/1 F/T is faster.

Asymmetric reduction of prochiral cyclic imines to alkaloid derivatives by novel asymmetric reducing reagent in THF or under solid-state conditions

Asymmetric reductions of prochiral cyclic imines were studied using chiral nonracemic sodium acyloxy borohydride 2. The chiral nonracemic reducing agent 2 has been easily prepared by the reaction of NaBH4 with N,N- phthaloyl amino acid 1 in THF

Asymmetric synthesis of (s)-norlaudanosine and (s)-tetrahydrohomopapaverine by catalytic asymmetric hydrogenation with chiral diphosphine-iridium(i)-phthalimide complex catalysts

Optically active 1,2,3,4-tetrahydroisoquinoline alkaloids, (S)-norlaudanosine and (S)-tetrahydrohomopapaverine, were prepared by catalytic asymmetric hydrogenation of 1-substituted 3,4-dihydro-6,7-dimethoxyisoquinolines with 1 mol % of an iridium(I) compl

Enantioselective Synthesis of R-(-)- and S-(+)-Cryptostyline II

Enantioselective synthesis of the title alkaloids using borohydride reduction of acyliminium ion, derived from prochiral 1-(3-,4-dimethoxyphenyl)-3,4-dihydro-6,7-dimethoxyisoquinoline and chiral acid chlorides is described. - Key words: isoquinoline alkal

Asymmetric Reduction of Cyclic Imines with Chiral Sodium Acyloxyborohydrides

Asymmetric reduction of prochiral cyclic imines with chiral sodium acyloxyborohydrides (5a-i), which are easily prepared by the reaction of NaBH4 with various N-acyl α-amino-acids, has been investigated.Of these new reducing agents, triacyloxyborohydrides (5c-f), derived from NaBH4 (1 equiv.) and (S)-N-acylproline (3 equiv.), were found to reduce 3,4-dihydropapaverine (2) in tetrahydrofuran to (S)-norlaudanosine (3) hydrochloride in 60percent optical yield.The N-benzyloxycarbonyl derivative (5c) could be isolated as a powder and characterized.The effect of solvents on this asymmetric reduction has been examined by the use of the isolated reagent (5c); halogenated alkane solvents such as CH2Cl2 or CHCl2CH3 gave a better optical yield of compound (3) (79percent e.e.).The reagent (5c) also reduced other cyclic imines (6a-c) and (8) to the corresponding alkaloids (7a-c) and (9) in excellent optical yields (70-86percent e.e.), providing an effective route to the asymmetric synthesis of these alkaloids.A possible reaction path for this reduction is also presented.

A Novel Asymmetric Reduction of Imines with Chiral Sodium Triacyloxyborohydrides

There has been described a novel and convenient synthesis of optically active alkaloids by the asymmetric reduction of cyclic imines using the chiral sodium triacyloxyborohydrides, easily prepared from the reaction of NaBH4 and N-acyl L-prolines.