14301-36-1Relevant articles and documents
13C NMR ANALYSIS OF SOME SIMPLE TETRAHYDROISOQUINOLINES
Mata, Rachel,Chang, Ching-Jer,McLaughlin, Jerry L.
, p. 1263 - 1270 (1983)
13C NMR resonances of 15 simple tetrahydroisoquinolines have been assigned on the basis of chemical shift theory, 13C-1H coupling constants and deuterium labelling at specific positions.The chemical shifts of both aliphatic and aromatic protons were correlated with substituent effects. - Key Words : 13C NMR spectra; cactus alkaloids; simple tetrahydroisoquinolines; carnegine; heliamine; lemaireocereine; longimammatine; lophophorine; N-methylanhalinine; O-methylcorypalline; O-methyluberine; nortehuanine; tehuanine; weberidine.
A concise, regio and stereoselective route to fluorinated protoberberines via tandem addition-cyclisation reactions of phthalide anions with 3,4-dihydroisoquinolines
Warrener, Ronald N.,Liu, Ligong,Russell, Richard A.
, p. 7485 - 7496 (1998)
A series of fluorinated protoberberines have been prepared by condensing fluorinated phthalide anions with 6,7-dimethoxydihydroisoquinoline. The spectroscopy and stereochemistry of the products are discussed and the stereochemical outcome of the reactions rationalised.
One-pot method for preparing 6,7-dimethoxy-3,4-dihydroisoquinoline hydrochloride
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Paragraph 0061-0062, (2020/03/09)
The invention provides a one-pot method for preparing 6,7-dimethoxy-3,4-dihydroisoquinoline hydrochloride. The method comprises the following steps: with 3,4-dimethoxyphenylethylamine and a formylation reagent as raw materials, carrying out a reaction to prepare an intermediate solution, and subjecting the prepared intermediate solution to a further reaction with a solution containing oxalyl chloride; after the reaction is finished, adding phosphotungstic acid for catalytic cyclization; then adding an alcohol solvent for oxalic acid removal to obtain a target product; and finally, cooling andcrystallizing a reaction solution, carrying out filtering, leaching a filter cake, and carrying out drying to obtain the target product. According to the invention, process operation is extremely simple, and the 6,7-dimethoxy-3,4-dihydroisoquinoline hydrochloride (with a purity of 99.0% or above and a single impurity content of less than or equal to 0.15%) meeting the cGMP quality index requirements and having yield of 75% or above can be obtained only by cooling, filtering, leaching and drying after the one-pot reaction, so process material, manpower and equipment costs are obviously reduced;the process safety level of the method is obviously improved; waste materials are few; and good industrial application prospects are obtained.
Sequential One-Pot Vilsmeier-Haack and Organocatalyzed Mannich Cyclizations to Functionalized Benzoindolizidines and Benzoquinolizidines
Outin, Johanne,Quellier, Pauline,Bélanger, Guillaume
, p. 4712 - 4729 (2020/03/30)
The development of new one-pot sequential cyclizations involving a Vilsmeier-Haack reaction followed by an organocatalyzed Mannich reaction is reported. This synthetic strategy gives access to functionalized indolizidines and quinolizidines in one operation from readily synthesized precursors. Yields and diastereoselectivities are good to excellent when formamides are used to trigger the key step, bearing either an electron-rich aryl or a pyrrole as the nucleophilic partner in the first cyclization.
Catalyst-Free Transamidation of Aromatic Amines with Formamide Derivatives and Tertiary Amides with Aliphatic Amines
Yin, Jiawen,Zhang, Jingyu,Cai, Changqun,Deng, Guo-Jun,Gong, Hang
supporting information, p. 387 - 392 (2019/01/11)
A simple catalyst- and promoter-free protocol has been developed for the transamidation of weakly nucleophilic aromatic amines with formamide derivatives and low-reactivity tertiary amides with aliphatic amines. This strategy is advantageous because no catalyst or promoters are needed, no additives are required, separation and purification is easy, and the reaction is scalable. Significantly, this strategy was further applied to synthesize several pharmaceutical molecules on a gram scale, and excellent yields were achieved.
