Category: 91-21-4

1,2,3,4-Tetrahydroisoquinoline, cas is 91-21-4, it is a common heterocyclic compound, the tetrahydroisoquinoline compound, its synthesis route is as follows.

A. 7-Nitro-1,2,3,4-tetrahydro-isoquinoline To 43.1 g (324 mmol) of 1,2,3,4-tetrahydro-isoquinoline was added 160 mL of concentrated sulfuric acid with ice bath cooling. Potassium nitrate 35.2 g (348 mmol) was added in portions to the stirring mixture, while maintaining an internal temperature below 5 C. The mixture was allowed to stand at ambient temperature for 72 h, and then basified with aqueous ammonia and extracted four times with chloroform. The combined organics were dried over MgSO4 and concentrated to give a dark brown oil. The oil was dissolved in 240 mL of ethanol and 40 mL of concentrated hydrochloric acid was added to the mixture with cooling. The precipitated material was collected by filtration and washed with cold ethanol to give 25.0 g of a tan solid. The crude material was partitioned between 1 N NaOH and ethyl acetate. The ethyl acetate layer was washed once with brine, dried over Na2 SO4 and concentrated. The dinitrated tetrahydroisoquinoline was removed by crystallization from ether/hexanes. The mother liquor was concentrated to give 2.19 g of 7-Nitro-1,2,3,4-tetrahydro-isoquinoline. B.[{1-[1-(R)-Benzyloxymethyl-2-(7-nitro-3,4-dihydro-1H-isoquinolin-2-yl)-2-oxo-ethylcarbamoyl]-1-methyl-ethyl]-carbamic acid tert-butyl ester According to General Procedure A, 100 mg (0.57 mmol) of 6A and 228 mg (0.60 mmol) of 3 were coupled, and the product was purified by silica gel chromatography (99:1 v/v CH2 Cl2:MeOH) to give 220 mg of 6B as a white foam., 91-21-4

With the rapid development of chemical substances, we look forward to future research findings about 91-21-4

Reference£º
Patent; Pfizer Inc; US5936089; (1999); A;,
Tetrahydroisoquinoline – Wikipedia
1,2,3,4-Tetrahydroisoquinoline | C9H11N – PubChem

91-21-4, 1,2,3,4-Tetrahydroisoquinoline is a tetrahydroisoquinoline compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

1,2,3,4-Tetrahydroisoquinoline (50 g; 1 equiv.) was added at 0¡ã C., in the course of 90 minutes, to 185 ml of sulfuric acid, and the reaction mixture was stirred for 30 minutes at 0¡ã C. Potassium nitrate (40.7 g; 1.2 equiv.) was then added in portions, and stirring was carried out for 15 hours at room temperature. When the conversion was complete, the reaction mixture was shaken on 500 g of ice and adjusted to pH 8-9 with ammonia solution. Extraction with chloroform was then carried out 3 times, and the combined organic phases were dried over sodium sulfate and concentrated under reduced pressure. The residue was taken up in IPA (500 ml) and cooled to 0¡ã C., and hydrochloric acid (2 equiv.) was added. The resulting solid was filtered out and recrystallised from methanol. 7-Nitro-1,2,3,4-tetrahydroisoquinoline (35 g; 52.3percent) was obtained in the form of a white solid.

As the paragraph descriping shows that 91-21-4 is playing an increasingly important role.

Reference£º
Patent; Gruenenthal GmbH; US2010/234340; (2010); A1;,
Tetrahydroisoquinoline – Wikipedia
1,2,3,4-Tetrahydroisoquinoline | C9H11N – PubChem

91-21-4, 1,2,3,4-Tetrahydroisoquinoline is a tetrahydroisoquinoline compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

1,2,3,4-tetrahydroisoquinolin (10. Og, 75.1mmol, 1 equiv) was dissolved in 40ml of concentrated sulfuric acid (exothermic reaction) and potassium nitrate (8.4g, 83.0mmol,1.1 equiv) was added in portions over lhour whilst stirring at O0C. The reaction mixture was then warmed up to room temperature and stirred for 2hrs. The reaction was poured in ice-water (100ml) and basified to pH 10 with ammonia solution (100ml). The mixture was then extracted with chloroform (2 x 250ml). The combined extracts were washed with brine, dried over magnesium sulfate and concentrated to give a dark red oil. The residue was purified by column chromatography using DCM/MeOH/NH4OH:95/5/0.5 to give the title mixture of isomers as a solid (7g, 52%).1H NMR (CDCl3, 400MHz) delta= 7.99 (m, IH), 7.92 (s, IH), 7.28 (m, IH), 7.26 (m, IH), 4.1 (s, 2H), 3.17 (m, 2H), 2.9 (m, 2H).

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Reference£º
Patent; CELLZOME AG; WO2009/62658; (2009); A1;,
Tetrahydroisoquinoline – Wikipedia
1,2,3,4-Tetrahydroisoquinoline | C9H11N – PubChem

91-21-4, 1,2,3,4-Tetrahydroisoquinoline is a tetrahydroisoquinoline compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

In a mortar 2 g of P2O5/silica gel (65% w/w)1 (10 mmol) and 1,2,3,4-tetrahydroisoquinoline (10 mmol, 1.33 g) was triturated for 30 s, and then 5 ml of HNO3 65% was added drop-wise and the mixture was further triturated with a pestle at room temperature for 20 min until a deep-yellow color appeared, at which point TLC (n-hexane:EtOAc 70:30) showed complete disappearance of 1,2,3,4-tetrahydroisoquinoline (30 min). To the reaction mixture was added diethyl ether (50 ml) and the solid was separated through a short pad of silica gel and washed with diethyl ether (2 ¡Á 15 ml). The filtrate was washed with NaHCO3 10% (20 ml) and dried (MgSO4). The solvent was evaporated under reduced pressure and the residue was purified by column chromatography (n-Hexane:EtOAc, 2:1), 7-nitro-1,2,3,4-tetrahydroisoquinoline (2b) was obtained (8 mmol, 1.4 g 80%) as a yellow solid, mp 121 C. 1H NMR, delta: 8.05 (m, 2H), 7.60 (m, 1H,), 3.82 (s, 2H), 3.38 (t, 2H, J = 7.4 Hz), 3.12 (t, 2H, J = 7.4 Hz), 2.83 (s, 1H). 13C NMR, delta: 150.6, 145.0, 140.3, 129.6, 122.6, 121.4, 46.9, 44.1, 28.1. EMS [M+H+] for C9H10N2O2, Calcd 179.0740. Found, 179.1121.

The synthetic route of 91-21-4 has been constantly updated, and we look forward to future research findings.

Reference£º
Article; Hajipour, Abdol R.; Guo, Lian-Wang; Pal, Arindam; Mavlyutov, Timur; Ruoho, Arnold E.; Bioorganic and Medicinal Chemistry; vol. 19; 24; (2011); p. 7435 – 7440;,
Tetrahydroisoquinoline – Wikipedia
1,2,3,4-Tetrahydroisoquinoline | C9H11N – PubChem

91-21-4, 1,2,3,4-Tetrahydroisoquinoline is a tetrahydroisoquinoline compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

(a) 1,2,3,4-Tetrahydroisoquinoline (50 g, 0.376M) was dissolved in concentrated H2 SO4 (180 ml) with cooling. Solid potassium nitrate (40.4 g, 0.4M) was added in portions, keeping the temperature below 5¡ã C., over 4 hours. The reaction mixture was allowed to stand overnight at room temperature and was then poured onto ice, basified with NH4 OH and was then extracted with CHCl3. After evaporation, the residue was dissolved in ethanol and concentrated HCl was added. The resulting precipitated hydrochloride salt was filtered off and recrystallized from methanol to yield 7-nitro-1,2,3,4-tetrahydroisoquinoline hydrochloride (31.5 g, 39percent), m.p. 268¡ã-269¡ã C.

The synthetic route of 91-21-4 has been constantly updated, and we look forward to future research findings.

Reference£º
Patent; SmithKline & French Laboratories, Ltd.; US4812573; (1989); A;,
Tetrahydroisoquinoline – Wikipedia
1,2,3,4-Tetrahydroisoquinoline | C9H11N – PubChem

91-21-4, 1,2,3,4-Tetrahydroisoquinoline is a tetrahydroisoquinoline compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

Step 1 Conc. sulfuric acid (80 ml) was added by small portions to tetrahydroisoquinoline (24.4 g, 183 mmol) under ice-cooling for dissolution. Then, 60percent nitric acid (18 ml) was added dropwise from a funnel and the mixture was stirred under ice-cooling for 3 hr. The mixture was stirred at room temperature for 18 hr. The reaction mixture was diluted with water under ice-cooling, and 35percent aqueous sodium hydroxide solution was added to adjust the solution to pH 12. After extraction with chloroform, the organic layer was washed with water, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was dissolved in ethanol (180 ml) and conc. hydrochloric acid (20 ml) was added under ice-cooling. The precipitated brown crystals were collected by filtration with suction to give 7-nitrotetrahydroisoquinoline hydrochloride (7.18 g, 22percent).

The synthetic route of 91-21-4 has been constantly updated, and we look forward to future research findings.

Reference£º
Patent; Japan Tobacco Inc.; US6410561; (2002); B1;,
Tetrahydroisoquinoline – Wikipedia
1,2,3,4-Tetrahydroisoquinoline | C9H11N – PubChem

91-21-4, 1,2,3,4-Tetrahydroisoquinoline is a tetrahydroisoquinoline compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

To 11 mL of 9 concentrated sulfuric acid in an ice bath was added 0 1,2,3,4-tetrahydroisoquinoline (2.9 g, 21 mmol), and 0 potassium nitrate (2.4 g, 24 mmol) was added slowly. The mixture was allowed to increase to room temperature and react overnight. Then the reaction liquid was poured into ice water, and pH was adjusted to around 10 with concentrated aqueous ammonia. After extraction with DCM three times, organic layers were combined and dried over anhydrous Na2SO4. After filtration, the solvent was evaporated under reduced pressure to obtain oil. The oil was dissolved in 16 mL of ethanol in an ice bath, and 3 mL of concentrated HCl was added to generate plenty of solid, which was subjected to suction filtration and drying. After recrystallization with methanol, 1.9 g of beige solid was obtained with a yield of 42percent.

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Reference£º
Patent; Peking University; Zhengzhou Granlen Pharmatech. Ltd.; LI, Runtao; AN, Haoyun; HAN, Liqiang; GE, Zemei; CUI, Jingrong; CHENG, Tieming; (52 pag.)EP3363803; (2018); A1;,
Tetrahydroisoquinoline – Wikipedia
1,2,3,4-Tetrahydroisoquinoline | C9H11N – PubChem