15248-39-2

Usage

Uses

Used in Chemical Synthesis:
6,7-Dimethoxyisoquinoline is used as an organocatalyst for the chemoselective O-tert-butoxycarbonylation of phenols. This application takes advantage of its ability to facilitate specific chemical reactions, leading to the formation of desired products with high selectivity and efficiency.
In the pharmaceutical industry, 6,7-dimethoxyisoquinoline can be used as a key intermediate in the synthesis of various bioactive compounds, including potential drug candidates. Its unique structure allows for further functionalization and modification, making it a valuable building block in the development of new medications.
Additionally, 6,7-dimethoxyisoquinoline may find applications in the field of materials science, where its properties can be exploited to design and synthesize novel materials with specific characteristics, such as improved stability, reactivity, or selectivity.

Synthesis Reference(s)

Journal of the American Chemical Society, 79, p. 3773, 1957 DOI: 10.1021/ja01571a043Synthesis, p. 288, 1974Tetrahedron Letters, 13, p. 4789, 1972

InChI:InChI=1/C11H11NO2/c1-13-10-5-8-3-4-12-7-9(8)6-11(10)14-2/h3-7H,1-2H3

Upstream product

• 3382-18-1 6,7-dimethoxy-3,4-dihydro-isoquinoline 
• 91569-96-9 6,7-dimethoxy-isoquinoline-1-carboxylic acid 
• 58163-19-2 dimethoxy-3,4 benzylideneaminoacetal diethylique 
• 1745-07-9 6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline 
• 39964-92-6 N-(3,4-dimethoxybenzyl)-N-(2,2-dimethoxyethyl)-4-methylbenzenesulfonamide 
• 24186-50-3 4-((E)-2-Isocyanato-vinyl)-1,2-dimethoxy-benzene 
• 522-57-6 papaveraldine 
• 7664-93-9 sulfuric acid 
• 32871-88-8 N-(3,4-dimethoxybenzyl)aminoacetaldehyde diethyl acetal 
• 7778-39-4 orthoarsenic acid 
• 946835-21-8 2-[(+)-10-camphorsulfonyl]-1-cyano-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline 
• 52095-39-3 2-ethenyl-4,5-dimethoxybenzaldehyde 
• 5392-10-9 2-bromo-4,5-dimethoxybenzaldehyde 
• 5293-43-6 1-bromo-4,5-dimethoxy-2-vinylbenzene 

Downstream Products

• 64434-29-3 2-benzyl-6,7-dimethoxyisoquinolin-1(2H)-one 
• 50299-95-1 2-benzoyl-1-cyano-6,7-dimethoxy-1,2-dihydroisoquinoline 
• 3428-75-9 N-methyl-6,7-dimethoxyisoquinolinium iodide 
• 138977-21-6 6,7-Dimethoxy-1-methyl-1H-isoquinoline-2-carboxylic acid (1S,2R,5S)-5-methyl-2-(1-methyl-1-phenyl-ethyl)-cyclohexyl ester 
• 77287-52-6 2--6,7-dimethoxy-1,2-dihydroisoquinaldonitrile 
• 93631-45-9 6,7-Dimethoxy-2-ethoxycarbonyl-1,2-dihydroisoquinaldonitrile 
• 21560-29-2 1-chloro-6,7-dimethoxyisoquinoline 
• 490-11-9 3,4-pyridinecarboxylic acid 
• 577-68-4 m-hemipinic acid 
• 102003-17-8 6,7-dimethoxy-2-(4-methoxy-benzoyl)-1,2-dihydro-isoquinoline-1-carbonitrile 
• 102311-65-9 (+/-)-2-trans-cinnamoyl-6,7-dimethoxy-1,2-dihydro-isoquinoline-1-carbonitrile 

Relevant academic research and scientific papers

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.

Rh/TiO2-Photocatalyzed Acceptorless Dehydrogenation of N-Heterocycles upon Visible-Light Illumination

TiO2 is an effective and extensively employed photocatalyst, but its practical use in visible-light-mediated organic synthesis is mainly hindered by its wide band gap energy. Herein, we have discovered that Rh-photodeposited TiO2 nanoparticles selectively dehydrogenate N-heterocyclic amines with the concomitant generation of molecular hydrogen gas in an inert atmosphere under visible light (λmax = 453 nm) illumination at room temperature. Initially, a visible-light-sensitive surface complex is formed between the N-heterocycle and TiO2. The acceptorless dehydrogenation of N-heterocycles is initiated by direct electron transfer from the HOMO energy level of the amine via the conduction band of TiO2 to the Rh nanoparticle. The reaction condition was optimized by examining different photodeposited noble metals on the surface of TiO2 and solvents, finding that Rh0 is the most efficient cocatalyst, and 2-propanol is the optimal solvent. Structurally diverse N-heterocycles such as tetrahydroquinolines, tetrahydroisoquinolines, indolines, and others bearing electron-deficient as well as electron-rich substituents underwent the dehydrogenation in good to excellent yields. The amount of released hydrogen gas evinces that only the N-heterocyclic amines are oxidized rather than the dispersant. This developed method demonstrates how UV-active TiO2 can be employed in visible-light-induced synthetic dehydrogenation of amines and simultaneous hydrogen storage applications.

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.

One-Pot Synthesis of Papaverine Hydrochloride and Identification of Impurities

Abstract: A one-pot synthesis of papaverine hydrochloride with 99.6% purity was performed using xylene as solvent for the entire process. The critical parameters of each step, as well as the impurities generated, were identified. The overall yield was improved to 63%. The proposed synthetic procedure is suitable for industrial production.

Visible-Light-Mediated Photocatalytic Aerobic Dehydrogenation of N-heterocycles by Surface-Grafted TiO2 and 4-amino-TEMPO

Herein, the visible-light-induced dehydrogenation of N-heterocycles such as tetrahydroquinolines, tetrahydroisoquinolines, and indolines in O2-containing suspensions of a commercially available titanium dioxide photocatalyst yielding the corresponding heteroarenes is presented. 4-Amino-2,2,6,6-tetramethylpipiridinyloxyl (4-amino-TEMPO) was found to exhibit a beneficial role, as it increased the yield and improved the selectivity of the dehydrogenation reaction. Both the selectivity and the yield are further enhanced by grafting 0.1 wt % of Ni(II) ions onto the TiO2 surface. It is proposed that the basic reactant adsorbs at Lewis acid sites present at the TiO2 surface. The dehydrogenation reaction is initiated by visible-light excitation of the resulting surface complex and a subsequent single-electron transfer from the excited N-heterocycle via the conduction band of TiO2 to O2. Ni(II) ions possibly serve as an electron transfer bridge between the conduction band of TiO2 and O2, while the TEMPO derivative is assumed to act as a selective redox mediator involved in reactions of the generated reactive oxygen species.

Metal-Free Dehydrogenation of N-Heterocycles by Ternary h-BCN Nanosheets with Visible Light

An efficient metal-free catalytic system has been developed based on hexagonal boron carbon nitride (h-BCN) nanosheets for the dehydrogenation of N-heterocycles with visible light; hydrogen gas is released in the process, and thus no proton acceptor is needed. This acceptorless dehydrogenation of hydroquinolines, hydroisoquinolines, and indolines to the corresponding aromatic N-heterocycles occurred in excellent yield under visible-light irradiation at ambient temperature. With h-BCN as the photocatalyst and water as the solvent, this environmentally benign protocol shows broad substitution tolerance and high efficiency.

One substrate, two modes of C-H functionalization: A metal-controlled site-selectivity switch in C-H arylation reactions

A unique site-selectivity switch has been achieved in the ruthenium-catalyzed C-H arylation reaction of N-acetyl-1,2-dihydroisoquinolines. This metal-mediated switch is antipodal to the previous report on the palladium-mediated C-4 C-H arylation on the same substrate. Mechanistic details reveal interesting aspects of the reaction pathway, and kinetic studies bring out the difference in the modes of C-H activation adopted by the two catalytic systems.

Dehydrogenation of Nitrogen Heterocycles Using Graphene Oxide as a Versatile Metal-Free Catalyst under Air

Graphene oxide (GO) has been developed as an inexpensive, environmental friendly, metal-free carbocatalyst for the dehydrogenation of nitrogen heterocycles. Valuable compounds, such as quinoline, 3,4-dihydroisoquinoline, quinazoline, and indole derivatives, have been successfully used as substrates. The investigation of various oxygen-containing molecules with different conjugated systems indicated that both the oxygen-containing groups and large π-conjugated system in GO sheets are essential for this reaction. (Figure presented.).

Synthesis method of quinoline compound

The invention discloses a synthesis method of a quinoline compound. The synthesis method of the quinoline compound comprises the following steps: taking a tetrahydroquinoline compound expressed in formula which is as shown in the description as a raw material, taking boron carbon nitrogen as a photocatalyst, adding a solvent, an oxidant and alkali, reacting under visible light radiation condition at room temperature, and purifying a reaction solution and then obtaining the quinoline compound; boron carbon nitrogen (h-BCNx) is a semiconductor polymer photocatalyst which has response to visible light and is free of metal elements; the semiconductor polymer photocatalyst has the advantages of low cost, high availability, high chemical stability, no toxicity, no harm and appropriate forbidden bandwidth and position of energy band; when the catalyst is applied to organic synthesis, the reaction process is simple to operate; the conditions are mild; the catalysis effect is excellent; the conversion rate can reach 90% or more; the yield of target products can reach 95%. The synthesis method of the quinoline compound is simple in process and low in cost, can meet the requirements of practical production, and has relatively great application potential.

Oxidation and deprotection of primary benzylamines by visible light flavin photocatalysis

We report a photocatalytic oxidation procedure that can be used to convert benzylamines into their corresponding aldehydes under mild conditions without over-oxidation, using riboflavin tetraacetate as photocatalyst and blue emitting LEDs (440 nm) as light source. Oxygen is the terminal oxidant and H 2O2 and NH3 appear as the only byproducts of the oxidation of primary benzylamines. Furthermore, we have developed a photocatalytic protocol for 4-methoxybenzyl (Mob) group deprotection of primary amines and alcohols. Double bonds, benzyl-protected esters and alcohols are tolerated under the applied conditions, whereas the deprotection of protected secondary amines is not applicable. Mob-protected carboxylic acids and carboxybenzoyl (Cbz) protected amines are inert under the photodeprotection conditions. Georg Thieme Verlag Stuttgart - New York.