less reactive aryl bromides as arylating reagents in the Pd(II)-catalyzed intermolecular arylation of unactivated C(sp3)–Hbonds is described. This reaction was promoted by a crucial 8-aminoquinolinyl directing group and a K2CO3 base, enabling regiospecific installation of an aryl scaffold at the β-position of carboxamides. A mechanistic study by DFT calculations reveals a C(sp3)–H activation-led
描述了在Pd(II)催化的未活化C(sp 3)-H键的分子间芳基化中使用容易获得的,反应性较低的芳基溴化物作为芳基化试剂的示例。至关重要的8-氨基喹啉基导向基团和K 2 CO 3碱促进了该反应,从而使芳基骨架可以在羧酰胺的β-位上进行区域特异性安装。通过DFT计算进行的机理研究揭示了C(sp 3)–H活化为主导的途径,该途径的特征是氧化加成为最高能量跃迁状态。
Catalytic, Regioselective Hydrocarbofunctionalization of Unactivated Alkenes with Diverse C–H Nucleophiles
作者:Kin S. Yang、John A. Gurak、Zhen Liu、Keary M. Engle
DOI:10.1021/jacs.6b08850
日期:2016.11.9
constructed from two classes of commonly available starting materials, alkenes and carbon-hydrogen (C-H) bonds. The reaction employs a palladium(II) catalyst and utilizes a removable directing group to both control the regioselectivity of carbopalladation and enable subsequent protodepalladation. A wide range of alkenes and C-H nucleophiles, including 1,3-dicarbonyls, aryl carbonyls, and electron-rich aromatics
形成碳-碳 (CC) 键的反应是有机合成的基石,广泛应用于化学科学。我们报告了一种转化,该转化使 CC 键能够由两类常用的起始材料、烯烃和碳氢 (CH) 键构成。该反应使用钯 (II) 催化剂并利用可去除的导向基团来控制碳钯化的区域选择性并实现随后的原脱钯。广泛的烯烃和 CH 亲核试剂,包括 1,3-二羰基化合物、芳基羰基化合物和富电子芳烃,都是可行的反应伙伴,使迈克尔型反应性从 α,β-不饱和羰基化合物扩展到未活化的烯烃。描述了这种转化在药物多样化和天然产物全合成中的应用。
Scope and Limitations of Auxiliary-Assisted, Palladium-Catalyzed Arylation and Alkylation of sp<sup>2</sup> and sp<sup>3</sup> C–H Bonds
作者:Enrico T. Nadres、Gerson Ivan Franco Santos、Dmitry Shabashov、Olafs Daugulis
DOI:10.1021/jo4013628
日期:2013.10.4
auxiliary-assisted direct arylation and alkylation of sp2 and sp3 C–H bonds of amine and carboxylic acid derivatives has been investigated. The method employs a palladium acetate catalyst, substrate, aryl, alkyl, benzyl, or allyl halide, and inorganic base in tert-amyl alcohol or water solvent at 100–140 °C. Aryl and alkyl iodides as well as benzyl and allyl bromides are competent reagents in this transformation
An efficient and convenient method has been developed to achieve direct silylation of unactivated remote primary or secondary C(sp3)-H bonds to form C-Si bonds with hexamethyldisilane (HMDS). This method highlights...
Palladium(<scp>ii</scp>)-catalyzed γ-selective hydroarylation of alkenyl carbonyl compounds with arylboronic acids
作者:Rei Matsuura、Tanner C. Jankins、David E. Hill、Kin S. Yang、Gary M. Gallego、Shouliang Yang、Mingying He、Fen Wang、Rohan P. Marsters、Indrawan McAlpine、Keary M. Engle
DOI:10.1039/c8sc03081b
日期:——
A catalytic γ-selective syn-hydroarylation of alkenyl carbonyl compounds using arylboronic acids has been developed using a substrate directivity approach with a palladium(II) catalyst. This method tolerates a wide range of functionalized (hetero)arylboronic acids and a variety of substitution patterns on the alkene. Preliminary mechanistic studies suggest that transmetalation is rate-limiting.
使用芳基硼酸对烯基羰基化合物进行催化γ-选择性顺式加氢芳基化反应,采用底物方向性方法和钯( II )催化剂进行开发。该方法可耐受多种官能化(杂)芳基硼酸和烯烃上的多种取代模式。初步机制研究表明金属转移是限速的。