4029-09-8

Upstream product

• 70216-31-8 N-(β-hydroxy-3,4-dimethoxy-phenethyl)-benzamide 
• 10172-51-7 6,7-dimethoxy-1-phenyl-3,4-dihydroisoquinoline 
• 460743-81-1 N-[2-(3,4-dimethoxyphenyl)-2-methoxyethyl]benzamide 
• 64-17-5 ethanol 
• 191113-01-6 6,7-Dimethoxy-1-phenyl-2-phenylmethanesulfonyl-1,2-dihydro-isoquinoline 
• 56139-08-3 (+/-)-(3,4-dimethoxyphenyl)phenylmethanol 
• 67616-16-4 N-[2-(3,4-dimethoxyphenyl)ethyl]benzamide 
• 100-52-7 benzaldehyde 
• 120-20-7 2-(3,4-dimethoxyphenyl)-ethylamine 
• 23818-68-0 1,2,3,4-tetrahydro-6,7-dimethoxy-2-[(4-methylphenyl)sulfonyl]-1-phenylisoquinoline 
• 4118-36-9 6,7-dimethoxy-1-phenyl-1,2,3,4-tetrahydroisoquinoline 
• 1370593-37-5 4,5-dimethoxy-2-(3-phenylallyl)benzaldehyde 
• 191112-95-5 N-(2,2-Dimethoxy-ethyl)-N-[(3,4-dimethoxy-phenyl)-phenyl-methyl]-C-phenyl-methanesulfonamide 
• 100-58-3 phenylmagnesium bromide 

Downstream Products

• 5833-05-6 6,7-dimethoxy-2-methyl-1-phenyl-isoquinolinium; iodide 
• 4008-69-9 6,7-dimethoxy-2-methyl-1-phenyl-1,2,3,4-tetrahydroisoquinoline 
• 178032-64-9 (R)-(+)-6,7-dimethoxy-1-phenyl-1,2,3,4-tetrahydroisoquinoline 
• 136905-00-5 (S)-(-)-6,7-dimethoxy-1-phenyl-1,2,3,4-tetrahydroisoquinoline 

Relevant academic research and scientific papers

Development of Pd(OAc)2-catalyzed tandem oxidation of C[sbnd]N, C[sbnd]C, and C(sp3)–H bonds: Concise synthesis of 1-aroylisoquinoline, oxoaporphine, and 8-oxyprotoberberine alkaloids

A catalytic tandem oxidation of C[sbnd]N, C[sbnd]C, and C(sp3)–H bonds is developed. This tandem oxidation is applied to two-step total syntheses of papaveraldine and pulcheotine A. Additionally, the total synthesis of liriodenine is achieved in six steps from homopiperonyl alcohol and 2-bromophenylacetonitrile by applying this catalytic tandem oxidation. Moreover, the direct conversion of xylopinine to 8-oxypseudopalmatine in a 76% yield demonstrates the versatility of this catalytic reaction.

A Visible-Light Promoted Amine Oxidation Catalyzed by a Cp*Ir Complex

Through a rapid screening of Cp*Ir complexes based on a turn-on type fluorescence readout, a [Cp*Ir(dipyrido[3,2-a : 2’,3’-c]phenazine)Cl]+ complex was found to catalyze the blue-light promoted dehydrogenation of N-heterocycles under physiological conditions. In the dehydrogenation of tetrahydroisoquinolines, the catalyst preferentially yielded the monodehydrogenated product, accompanying H2O2 generation. We surmise that this mechanism may be reminiscent of flavin-dependent oxidases.

Reusable, homogeneous water soluble photoredox catalyzed oxidative dehydrogenation of N-heterocycles in a biphasic system: Application to the synthesis of biologically active natural products

Herein, a simple and efficient method for the oxidative dehydrogenation (ODH) of tetrahydro-β-carbolines, indolines and tetrahydro-(iso)quinolines is described using a reusable, homogeneous cobalt-phthalocyanine photoredox catalyst in a biphasic medium. A biphasic system offers an advantage of easy separation of the product and an efficient reusability of the homogeneous photoredox catalyst. Also, the current system significantly helps to overcome the solubility issue of the substrate and catalyst at room temperature. Its potential applications to organic transformations are demonstrated by the synthesis of various biologically active N-heterocycles such as indoles, (iso)quinolines and β-carbolines and natural products such as eudistomin U, norharmane, and harmane and precursors to perlolyrine and flazin. Without isolation and purification, the catalyst solution can be reused up to 5 times with almost comparable reactivity. Furthermore, the efficiency of the reaction was demonstrated on a gram scale. To the best of our knowledge, this is the first report on ODH reactions using a non noble, reusable and homogeneous cobalt photoredox catalyst under environmentally friendly conditions.

Electrochemical Acceptorless Dehydrogenation of N-Heterocycles Utilizing TEMPO as Organo-Electrocatalyst

Catalytic acceptorless dehydrogenation (CAD) has been a basically important organic transformation to ubiquitous unsaturated compounds without the usage of a sacrificial hydrogen acceptor. In this work, we successfully developed the first electrochemical acceptorless dehydrogenation (ECAD) of N-heterocycles using TEMPO as the organo-electrocatalyst. We have achieved the catalytic dehydrogenation of N-heterocycles in an anode and the release of H2 in a cathode using an undivided-cell system. A variety of six-membered and five-membered nitrogen-heteroarenes can be synthesized in good yields in this system. In addition, this protocol can also be used in the application of important molecular synthesis. Our electrochemical strategy provides a mild and metal-free route for (hetero)aromatic compounds synthesis via the CAD strategy.

Method for solvent accelerated selective dehydrogenation of tetrahydroisoquinoline type compound

The invention discloses a method for synthesizing 1-substituted-3,4-dihydroisoquinoline through the solvent accelerated selective partial dehydrogenation of a 1-substituted-1,2,3,4-tetrahydroisoquinoline compound. For a simple and easily obtained cyclic amine type compound such as a tetrahydroisoquinoline compound, a corresponding imine compound can be obtained through selective dehydrogenation; the conversion ratio of the cyclic amine type compound is higher; further, the proportion of a partially dehydrogenated product to a fully dehydrogenated product is more than 20 to 1. The method is simple and convenient to operate, is practical, easy and feasible, and is mild in reaction condition; the actual cost is greatly reduced. In addition, a method for synthesizing 3,4-dihydroisoquinoline through the direct dehydrogenation of tetrahydroisoquinoline has the advantages of atom economy and environmental friendliness.

Cerium Chloride Catalyzed, 2-Iodoxybenzoic Acid Mediated Oxidative Dehydrogenation of Multiple Heterocycles at Room Temperature

Catalytic cerium chloride was found to activate 2-iodoxybenzoic acid (IBX) for the oxidative dehydrogenation of tetrahydroisoquinolines, tetrahydro-β-carbolines, and thiazolidines to their dehydrogenated and aromatic forms at room temperature in moderate to excellent yields. The robustness of the protocol was demonstrated by scaling up the reactions to multigram quantities.

Palladium carbon catalyzed selective partial dehydrogenation method of tetrahydroisoquinoline

The invention relates to a method for synthesis of 1-substituted-3, 4-dihydroisoquinoline by palladium carbon catalyzed selective partial dehydrogenation of a 1-substituted-1, 2, 3, 4-tetrahydroisoquinoline compound. The reaction temperature is 0-80DEG C. For easily available cyclic amine compounds like tetrahydroisoquinoline, a corresponding imine compound can be obtained through selective dehydrogenation, the conversion rate is up to 99%, and the proportion of a partial dehydrogenation product and a complete dehydrogenation product is greater than 20:1. The method provided by the invention has simple and practical operation, the raw materials and catalyst are cheap and easily available, the reaction conditions are mild, and the catalyst can be recycled, thus greatly reducing the actual cost. In addition, the method for synthesis of 3, 4-dihydroisoquinoline through direct dehydrogenation of tetrahydroisoquinoline has the advantages of atom economy and environmental friendliness.

Highly selective partial dehydrogenation of tetrahydroisoquinolines using modified Pd/C

A highly selective procedure has been developed for the partial dehydrogenation of 1-substituted-1,2,3,4-tetrahydroisoquinolines over K3PO4·3H2O-modified Pd/C catalyst. This new method provides facile, atom-economical and environmentally friendly access to 1-substituted-3,4-dihydroisoquinolines without the need for stoichiometric amounts of harmful oxidants. The use of standard Pd/C as a catalyst for this process gave poor chemoselectivity. Pleasingly, the use of a K3PO4·3H2O-modified Pd/C catalyst promoted the partial dehydrogenation of 1-substituted-1,2,3,4-tetrahydroisoquinolines with excellent chemoselectivity by suppressing further dehydroaromatization. Furthermore, conducting the reaction under an atmosphere of oxygen led to further improvements in the chemoselectivity of the dehydrogenation, with the ratio of imine to isoquinoline reaching up to 32/1. The heterogenous Pd/C catalyst could also be recycled and reused at least three times with excellent conversion and chemoselectivity, demonstrating the significantly practical potential of this methodology.

Acceptorless dehydrogenation of nitrogen heterocycles with a versatile iridium catalyst

Gas up: A cyclometalated iridium complex is found to catalyze the dehydrogenation of various benzofused N-heterocycles, thus releasing H 2. Driven by as low as 0.1 mol % catalyst, the reaction affords quinolines, indoles, quinoxalines, isoquinolines, and β-carbolines in high yields. Copyright

Facile synthesis of substituted isoquinolines

A facile three-step protocol toward methoxy isoquinolines 7 starting with substituted 2-allylbenzaldehydes 9 was described. The overall synthetic process of skeleton 7 was carried out using the Grignard addition, PCC-oxidation, and one-pot oxidative cleavage of the olefinic group of skeleton 9 with OsO 4-NaIO4 followed by the condensation of the resulting 1,5-dicarbonyl compounds with NH4OAc. Skeleton 9 was prepared in high yield via the known Claisen rearrangement of skeleton 8 and O-methylation. Papaverine 2 is also synthesized via the simple three-step synthetic protocol.