4073-42-1Relevant academic research and scientific papers
Covalent organic framework supported Pd(II)-catalyzed conjugate additions of arylboronic acids to α,β-unsaturated carboxylic acids
Wen, Min,Lu, Shujuan,Fan, Chaogang,Shen, Kai,Lin, Shaohui,Pan, Qinmin
, (2021/04/28)
A palladium(II)-coordinated covalent organic framework (Pd(II)@COF) was mechanochemically synthesized from [2,2′-bipyridine]-5,5′-diamine (Bpy) and 1,3,5-triformylphloroglucinol (Tp), which was demonstrated as a catalyst for conjugate addition of arylboronic acids to unreactive α,β-unsaturated carboxylic acids in aqueous media (water/acetone = 1:1). Modest to good yields were obtained for most substrates, and studies on the catalyst recyclability showed that the heterogeneous catalyst gave >80% yields in the first 4 cycles. This research broadens the application of COFs supported catalysis and gave a new option for Pd(II)-catalysis.
Cationic Pd(II)/bipyridine-catalyzed conjugate addition of arylboronic acids to α,β-unsaturated carboxylic acids in aqueous media
Ni, Yuxin,Song, Kaixuan,Shen, Kai,Yang, Zhenyu,Liu, Rui,Lin, Shaohui,Pan, Qinmin
supporting information, p. 1192 - 1195 (2018/03/01)
An in-situ generated cationic Pd(II)/bipyridine-catalyzed conjugate addition of arylboronic acids to α,β-unsaturated carboxylic acids in water was developed and optimized. For most substrates, nearly quantitative yields were given, and the products can be purified by simple washing without column chromatography. The reaction can be scaled up to 1.0 g easily with excellent yields. Also the loading of catalyst can be lowered to 1.0 mol% with modest yields, and the reaction provided a mild and easy way to synthesize β-disubstituted carboxylic acids.
Pd(II)/Bipyridine-Catalyzed Conjugate Addition of Arylboronic Acids to α,β-Unsaturated Carboxylic Acids. Synthesis of β-Quaternary Carbons Substituted Carboxylic Acids
Liu, Rui,Yang, Zhenyu,Ni, Yuxin,Song, Kaixuan,Shen, Kai,Lin, Shaohui,Pan, Qinmin
, p. 8023 - 8030 (2017/08/14)
Pd(II)/bipyridine-catalyzed conjugate addition of arylboronic acids to α,β-unsaturated carboxylic acids (including β,β-disubstituted acrylic acids) was developed and optimized, which provided a mild and convenient method for the highly challenging synthesis of β-quaternary carbons substituted carboxylic acids.
Construction of 3-arylpropylamines using Heck arylations. the total synthesis of cinacalcet hydrochloride, alverine, and tolpropamine
Prediger, Patrícia,Da Silva, Allan Ribeiro,Correia, Carlos Roque Duarte
, p. 3333 - 3341 (2014/05/06)
New synthetic routes toward the commercial drugs cinacalcet hydrochloride, alverine, and tolpropamine were developed using a Heck-Matsuda arylation as the key-step. Several reaction conditions were evaluated for the Heck-Matsuda reaction using allylamine derivatives and arenediazonium salts. For cinacalcet hydrochloride, N-formylamide provided the best result, furnishing the synthetic target in a very high overall yield (75% over five steps). For alverine, the best results were obtained using a double Heck-Matsuda strategy, providing alverine in an excellent overall yield (69%) from N-acetyl diallylamine in three steps. Tolpropamine was synthesized in a 46% yield over five steps using an efficient reductive Heck-Matsuda arylation between p-bromo-methylcinnamate with 3-chloro tolyldiazonium salt, generating the ,diaryl propionate that was converted to tolpropamine.
Ring-substituted histaprodifen analogues as partial agonists for histamine H1 receptors: Synthesis and structure-activity relationships
Elz, Sigurd,Kramer, Kai,Leschke, Christian,Schunack, Walter
, p. 41 - 52 (2007/10/03)
Thirteen racemic benzene ring-substituted analogues of histaprodifen (8a; 2-[2-(3,3-diphenylpropyl)-1H-imidazol-4-yl]ethanamine), a novel lead for potent and selective histamine H1-receptor agonists, have been prepared from substituted 4,4-diphenylbutyronitriles 5 via cyclization of the corresponding methyl butyrimidates 6 with 2-oxo-4-phthalimido-1-butyl acetate in liquid ammonia, followed by deprotection. Nitriles 5 were accessible by alkylation of either substituted diphenylmethanes with 3-bromopropionitrile or diethyl malonate with substituted 1-chloro-diphenylmethanes and subsequent standard reactions. The title compounds 8 displayed partial agonism on conctractile H1 receptors of the guinea-pig ileum (E(max) = 2-98% relative to histamine) and, compared with the endogenous agonist, were endowed with agonist potencies of 4-92%. The meta fluorinated (8c) and meta chlorinated (8f) analogues showed the highest relative potency in this series (95% confidence limits 85-99% and 78-102%), but did not exceed the value of the lead 8a (99- 124%). Compound 8c (2-[2-[3-(3-fluorophenyl)-3-phenylpropyl]-1H-imidazol-4- yl]ethanamine) was a partial agonist at contractile H1 receptors of the guinea-pig aorta (relative potency 154% vs. 100% for histamine) and at relaxation-mediating endothelial H1 receptors of the rat aorta (relative potency 556% vs. 100% for histamine) and matched with the functional behaviour of 8a. Agonism observed for each compound was sensitive to blockade by the selective H1-receptor antagonist mepyramine (pA2 ? 9 (guinea-pig) and pA2 ? 8 (rat aorta)). All histaprodifen analogues 8 stimulated neither histaminergic H2/H3 nor cholinergic M3 receptors. They displayed only low to moderate affinity for these sites (H2: pD'2 3/M3: pA2 1-receptor agonist, viz. 2- phenylhistamine. (C) 2000 Editions scientifiques et medicales Elsevier SAS.
