Introduction of a new synthetic route about 91-21-4

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