The Oxidative Mannich Reaction Catalyzed by Dirhodium Caprolactamate
摘要:
Dirhodium caprolactamate [Rh2(cap)4] is a highly effective catalyst for the oxidative Mannich reaction. The reaction proceeds via C-H oxidation of a tertiary amine followed by nucleophilic capture. This green transformation is conducted in protic solvent using inexpensive T-HYDRO (70% t-BuOOH in water). Synthetically valuable gamma-aminoalkyl butenolides are obtained.
The first B(C6F5)3‐catalyzed deoxygenative reduction of amides into the corresponding amines with readily accessible and stable ammonia borane (AB) as a reducing agent under mild reaction conditions is reported. This metal‐free protocol provides facile access to a wide range of structurally diverse amine products in good to excellent yields, and various functional groups including those that are reduction‐sensitive
据报道,在温和的反应条件下,用易于获得且稳定的氨硼烷(AB)作为还原剂,将酰胺进行的首次B(C 6 F 5)3催化脱氧还原为相应的胺。该无金属方案可轻松获得各种结构多样的胺产品,且收率高至优异,并且对各种官能团(包括对还原敏感的官能团)均具有良好的耐受性。该新方法也适用于手性酰胺底物,而不会破坏对映体的纯度。BF 3 OEt 2助催化剂在该反应中的作用是通过酰胺-硼加合物的原位形成来活化酰胺羰基。
Ru‐Catalyzed Deoxygenative Transfer Hydrogenation of Amides to Amines with Formic Acid/Triethylamine
ruthenium(II)‐catalyzed deoxygenative transfer hydrogenation of amides to amines using HCO2H/NEt3 as the reducing agent is reported for the first time. The catalyst system consisting of [Ru(2‐methylallyl)2(COD)], 1,1,1‐tris(diphenylphosphinomethyl) ethane (triphos) and Bis(trifluoromethane sulfonimide) (HNTf2) performed well for deoxygenative reduction of various secondary and tertiary amides into the corresponding
首次报道了使用HCO 2 H / NEt 3作为还原剂的钌(II)催化的酰胺脱氧转移胺成胺。催化剂体系由[Ru(2-甲基烯丙基)2(COD)],1,1,1-三(二苯基膦甲基)乙烷(triphos)和双(三氟甲烷磺酰亚胺)(HNTf 2)在将各种仲酰胺和叔酰胺脱氧还原成相应的胺方面表现出色,选择性极好,并且对包括还原敏感基团在内的官能团表现出很高的耐受性。氢源和酸助催化剂的选择对于催化至关重要。机理研究表明,通过借入氢对原位生成的醇和胺进行还原胺化是主要途径。
Photochemical Decarboxylative C(sp<sup>3</sup>)–X Coupling Facilitated by Weak Interaction of N-Heterocyclic Carbene
作者:Kun-Quan Chen、Zhi-Xiang Wang、Xiang-Yu Chen
DOI:10.1021/acs.orglett.0c03006
日期:2020.10.16
still in its infancy. We demonstrate herein transition-metal-free decarboxylative C(sp3)–X bond formation enabled by the photochemical activity of the NHPI ester–NaI–NHC complex, giving primary C(sp3)–(N)phth, secondary C(sp3)–I, or tertiary C(sp3)–(meta C)phth coupling products. The primary C(sp3)–(N)phth coupling offers convenient access to primary amines.
Allylic Oxidations Catalyzed by Dirhodium Catalysts under Aqueous Conditions
申请人:Doyle Michael P.
公开号:US20090093638A1
公开(公告)日:2009-04-09
The present invention relates to compositions and methods for achieving the efficient allylic oxidation of organic molecules, especially olefins and steroids, under aqueous conditions. The invention concerns the use of dirhodium (II,II) “paddlewheel complexes, and in particular, dirhodium carboximate and tert-butyl hydroperoxide as catalysts for the reaction. The use of aqueous conditions is particularly advantageous in the allylic oxidation of 7-keto steroids, which could not be effectively oxidized using anhydrous methods, and in extending allylic oxidation to enamides and enol ethers.
One-Pot Synthesis of Secondary and Tertiary Amines by Carbonylative Hydroaminomethylation of Alkenes Catalyzed by Di(μ-chloro)bis(η4-1,5-cyclooctadiene)dirhodium
作者:Thorsten Rische、Peter Eilbracht
DOI:10.1055/s-1997-1338
日期:1997.11
Secondary and tertiary amines are selectively prepared with high yields by the reaction of alkenes with primary or secondary amines, carbon monoxide and hydrogen in the presence of [Rh(cod)Cl]2 as catalyst via a one-pot hydroformylation - amine condensation - reduction sequence.