170701-40-3

Upstream product

• 61-54-1 tryptamine 
• 123-11-5 4-methoxy-benzaldehyde 
• 100-09-4 4-methoxybenzoic acid 
• 296797-76-7 2,3,4,9-tetrahydro-1-(4-methoxyphenyl)-2-tosyl-1H-pyrido[3,4-b]indole 
• 3380-73-2 1-(4-methoxyphenyl)-1,2,3,4-tetrahydro-1H-pyrido[3,4-b]indole 

Downstream Products

• 1068158-72-4 (S)-1-(4-methoxyphenyl)-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indole 

Relevant academic research and scientific papers

Selectivity-tunable oxidation of tetrahydro-β-carboline over an OMS-2 composite catalyst: preparation and catalytic performance

Controlling the reaction selectivity of organic transformations without losing high conversion is always a challenge in catalytic processes. In this work, a H3PO4·12WO3/OMS-2 nanocomposite catalyst ([PW]-OMS-2) was prepared through the oxidation of a Mn(ii) salt with sodium phosphotungstate by KMnO4. Comprehensive characterization indicates that different Mn2+precursors significantly affected the crystalline phase and morphology of the as-synthesized catalysts and only MnSO4·H2O as the precursor could lead to a cryptomelane phase. Moreover, [PW]-OMS-2 demonstrated excellent catalytic activity toward aerobic oxidative dehydrogenation of tetrahydro-β-carbolines due to mixed crystalline phases, enhanced surface areas, rich surface oxygen vacancies and labile lattice oxygen species. In particular, β-carbolines and 3,4-dihydro-β-carbolines could be obtained from tetrahydro-β-carbolines with very high selectivity (up to 99%) over [PW]-OMS-2viatuning the reaction solvent and temperature. Under the present catalytic system, scalable synthesis of a β-carboline was achieved and the composite catalyst showed good stability and recyclability. This work not only clarified the structure-activity relationship of the catalyst, but also provided a practical pathway to achieve flexible, controllable synthesis of functional N-heterocycles.

Iodine-catalyzed chemoselective dehydrogenation and aromatization of tetrahydro-β-carbolines: A short synthesis of Kumujian-C, Eudistomin-U, Norharmane, Harmane Harmalan and Isoeudistomine-M

Temperature controlled chemoselective dehydrogenation and aromatization of tetrahydro-β-carbolines, using molecular I2 and H2O2, in DMSO solvent affords a practical access to a series of corresponding 3,4-dihydro-β-carbolines and β-carbolines respectively. This method has been successfully employed in the short synthesis of Kumujian-C, Eudistomin-U, Norharmane Harmane Harmalan and Isoeudistomin-M.

Development of a metal-free amine oxidation method utilizing DEAD chemistry

Herein, we examine the oxidative abilities of azodicarboxylates for the conversion of amines to imines. This method provides access to synthetically useful imine intermediates including β-carbolines, quinazolines and N-heterocyclic carbene precursors. The ability to recover spent azodicarboxylate for regeneration and further use underscores the applicability and appeal of this protocol.

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.

Synthetic study on the T3P-promoted one-pot preparation of 1-substituted-3,4-dihydro-β-carbolines by the reaction of tryptamine with carboxylic acids

A novel and efficient one-pot method has been developed for the synthesis of 1-substituted-3,4-dihydro-β-carbolines from tryptamine and a wide variety of carboxylic acids. The reaction was successfully applied to the synthesis of an important alkaloid har

N-Bromo-succinimide promoted synthesis of β-carbolines and 3,4-dihydro-β-carbolines from tetrahydro-β-carbolines

Herein, we report a facile synthesis of 3,4-dihydro-β-carbolines and aromatic β-carbolines from tetrahydro-β-carbolines, mediated by N-bromosuccinimide in toluene at 0°C to room temperature (rt), in good to moderate yields.

Cooperative dehydrogenation of N-heterocycles using a carbon nanotube-rhodium nanohybrid

Rhodium nanoparticles were anchored on carbon nanotubes and the resulting nanohybrid was studied as co-catalyst, along with tert-butylcatechol, for the dehydrogenation of various N-heterocycles. The co-catalytic system operates in high yields, under the mildest conditions reported so far, and can be applied to a wide variety of secondary amine-containing scaffolds.

Bioinspired aerobic oxidation of secondary amines and nitrogen heterocycles with a bifunctional quinone catalyst

Copper amine oxidases are a family of enzymes with quinone cofactors that oxidize primary amines to aldehydes. The native mechanism proceeds via an iminoquinone intermediate that promotes high selectivity for reactions with primary amines, thereby constraining the scope of potential biomimetic synthetic applications. Here we report a novel bioinspired quinone catalyst system consisting of 1,10-phenanthroline-5,6-dione/ZnI2 that bypasses these constraints via an abiological pathway involving a hemiaminal intermediate. Efficient aerobic dehydrogenation of non-native secondary amine substrates, including pharmaceutically relevant nitrogen heterocycles, is demonstrated. The ZnI2 cocatalyst activates the quinone toward amine oxidation and provides a source of iodide, which plays an important redox-mediator role to promote aerobic catalytic turnover. These findings provide a valuable foundation for broader development of aerobic oxidation reactions employing quinone-based catalysts.

Mild and efficient syntheses of 1-aryl-3,4-dihydroisoquinolines and 1-aryl-3,4-dihydro-β-carbolines via regiospecific β-eliminations of the corresponding N-tosyl-1,2,3,4-tetrahydroisoquinolines and N-tosyl-1,2,3,4-tetrahydro-β-carbolines

(Chemical Equation Presented) Treatment of N-tosyl-1-aryl-1,2,3,4- tetrahydro-isoquinolines or N-tosyl-1-aryl-1, 2,3,4-tetrahydro-β-carbolines with a strong base such as NaOH or KOH at 70 °C in dimethylsulfoxide (DMSO) produced 1-aryl-3,4-dihydroisoquinolines or 1-aryl-3,4-dihydro-β- carbolines in good yields via mild and regiospecific β-eliminations. A dramatic solvent effect was observed, DMSO was crucial for the reactions. The temperature is also crucial for the reactions and should be kept between 60 and 80 °C. Copyright Taylor & Francis Group, LLC.

Mild Oxidation of 1,2,3,4-Tetrahydro-β-carbolines

Oxidation of 1-(aryl or heteroaryl)-1,2,3,4-tetrahydro-β-carbolines (1a-r) with KMnO4 in dry THF afforded in the most cases almost exclusively 3,4-dihydro products (2) with a yield of 28-94percent.Only in few cases (1c, 1i, 1m) the reaction was non-selective and a significant amount of the fully aromatized products (3) (30-40percent of the reaction mixture) was observed.The influence of both the substituent nature and the substitution modes on the observed yield and selectivity of the reaction was discussed.Key words: 1,2,3,4-tetrahydro-β-carbolines, 3,4-dihydro-β-carbolines, selective oxidation, oxidation with KMnO4 in cold THF, substituent effect