Cu(I)-catalyzed synthesis of N- tosyl-4-iminoquinolizines
摘要:
Pyridines were found to be a convenient nucleophile in the copper(I)-catalyzed synthesis of N-tosyl-4-iminoquinolizines from 2-pyridyl compounds. Intramolecular cyclization of an in situ generated ketenimine and a tethered pyridine, followed by a base-promoted oxidation, affords the desired products in moderate to good yields under mild reaction conditions. (C) 2015 Elsevier Ltd. All rights reserved.
Room Temperature, Reductive Alkylation of Activated Methylene Compounds: Carbon–Carbon Bond Formation Driven by the Rhodium-Catalyzed Water–Gas Shift Reaction
作者:Scott E. Denmark、Malek Y. S. Ibrahim、Andrea Ambrosi
DOI:10.1021/acscatal.6b03183
日期:2017.1.6
The rhodium-catalyzed water–gas shift reaction has been demonstrated to drive the reductive alkylation of several classes of activated methylene compounds at room temperature. Under catalysis by rhodium trichloride (2–3 mol %), carbon monoxide (10 bar), water (2–50 equiv), and triethylamine (2.5–7 equiv), the scope has been successfully expanded to cover a wide range of alkylating agents, including
For the first time, a novel copper-catalyzed direct C(sp3)–H/C(sp3)–H cross-coupling of arylacetonitriles with unactivated benzylic compounds was described, allowing various a-benzylated arylacetonitriles to be readily accessible under base-free conditions. Mechanistic investigations suggested that the reaction proceeds through radical process and the C(sp3)–H cleavage of arylacetonitriles probably
Base‐Promoted α‐Alkylation of Arylacetonitriles with Alcohols
作者:Bivas Chandra Roy、Istikhar A. Ansari、Sk. Abdus Samim、Sabuj Kundu
DOI:10.1002/asia.201900285
日期:2019.7
A practical method to synthesize α‐alkylated arylacetonitriles from arylacetonitriles and alcohols without using any expensive transition metal complexes is demonstrated here. Following this base‐catalysed sustainable procedure, various arylacetonitriles were successfully alkylated with different alcohols. The practical applicability of this protocol was extended by one‐pot synthesis of important carboxylic
Sustainable Alkylation of Nitriles with Alcohols by Manganese Catalysis
作者:Jannik C. Borghs、Mai Anh Tran、Jan Sklyaruk、Magnus Rueping、Osama El-Sepelgy
DOI:10.1021/acs.joc.9b00792
日期:2019.6.21
A general and chemoselective catalytic alkylation of nitriles using a homogeneous nonprecious manganese catalyst is presented. This alkylation reaction uses naturally abundant alcohols and readily available nitriles as coupling partners. The reaction tolerates a wide range of functional groups and heterocyclic moieties, efficiently providing useful cyanoalkylated products with water as the only side
Chemoselective α-Alkylation and α-Olefination of Arylacetonitriles with Alcohols <i>via</i> Iron-Catalyzed Borrowing Hydrogen and Dehydrogenative Coupling
borrowing hydrogen or α-olefination by dehydrogenativecoupling methods. Designing and developing high-performance earth-abundant catalysts that can procure different products from the same starting materials remain a great challenge. Herein, we report an iron(0) catalyst system that achieves chemoselectivity between borrowing hydrogen and dehydrogenativecoupling protocols by simply changing the base. A
α-烷基腈和α-烯烃腈在有机合成和药物化学中非常重要。然而,不同类型的催化剂用于通过借氢实现腈的α-烷基化或通过脱氢偶联方法实现α-烯烃化。设计和开发高性能的地球丰富的催化剂,可以从相同的起始材料中获得不同的产品仍然是一个巨大的挑战。在此,我们报告了一种铁 (0) 催化剂系统,该系统通过简单地改变碱基来实现借氢和脱氢偶联方案之间的化学选择性。广泛的腈类和醇类,包括苄醇、直链脂肪醇、脂环醇、杂环醇和烯丙醇,被选择性且有效地转化为相应的产物。机理研究表明反应机理通过脱氢途径进行。这种铁催化方案对环境无害且原子效率高,可释放 H2和 H 2 O 作为绿色副产物。