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。
n of alkenes with anilines has been developed for the atom-economical synthesis of 2-substituted propanamides bearing an α-stereocenter. A novel phosphoramidite ligand L16 was discovered which exhibited very high reactivity and selectivity in the reaction. This asymmetric Markovnikov hydroaminocarbonylation employs readily available starting materials and tolerates a wide range of functional groups
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。
Binuclear Pd(I)–Pd(I) Catalysis Assisted by Iodide Ligands for Selective Hydroformylation of Alkenes and Alkynes
is driven by a novel activation strategy and features a unique Pd(I)-Pd(I) mechanism, involving an iodide-assisted binuclear step to release the product. This method enables β-selective hydroformylation of a large range of alkenes and alkynes, including sensitive starting materials. Its utility is demonstrated in the synthesis of antiobesity drug Rimonabant and anti-HIV agent PNU-32945. In a broader
Selective Palladium-Catalyzed Aminocarbonylation of Olefins with Aromatic Amines and Nitroarenes
作者:Xianjie Fang、Ralf Jackstell、Matthias Beller
DOI:10.1002/anie.201308455
日期:2013.12.23
Various olefins can be smoothly transformed in the presence of a Pd‐based catalyst system and (hetero)aromaticamines or nitroarenes to synthetically interesting amides in good yields and often with high regioselectivity (see scheme). Combining this atom‐efficient procedure with established functionalizations of the resulting products allows the efficient preparation of quinolines.
With advances in organoboron chemistry, boron-centered functional groups have become increasingly attractive. In particular, alkylboron species are highly versatile reagents for organic synthesis, but the direct generation of alkyl radicals from commonly used, bench-stable boron species has not been thoroughly investigated. Herein, we describe a method for activating C–B bonds by nitrogen- or oxygen-radical
随着有机硼化学的进步,以硼为中心的官能团变得越来越有吸引力。特别是,烷基硼物质是用于有机合成的高度通用的试剂,但从常用的、实验室稳定的硼物质直接生成烷基自由基尚未得到彻底研究。在此,我们描述了一种通过氮或氧自由基转移激活 C-B 键的方法,该方法适用于烷基硼酸和酯,并且可用于 Michael 加成反应和 Minisci 反应以生成烷基或芳基化产物。