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。
Highly Efficient CH Hydroxylation of Carbonyl Compounds with Oxygen under Mild Conditions
作者:Yu-Feng Liang、Ning Jiao
DOI:10.1002/anie.201308698
日期:2014.1.7
A transition‐metal‐free Cs2CO3‐catalyzed α‐hydroxylation of carbonylcompounds with O2 as the oxygen source is described. This reaction provides an efficient approach to tertiary α‐hydroxycarbonyl compounds, which are highly valued chemicals and widely used in the chemical and pharmaceutical industry. The simple conditions and the use of molecular oxygen as both the oxidant and the oxygen source make
描述了无过渡金属的Cs 2 CO 3催化的羰基化合物的α-羟基化,其中O 2为氧源。该反应为叔α-羟基羰基化合物提供了一种有效的方法,这些叔α-羟基羰基化合物是极有价值的化学物质,广泛用于化学和制药行业。简单的条件和使用分子氧作为氧化剂和氧源使该协议非常环保和实用。此转换是高效的,并且对叔C(sp 3)H键裂解具有高度选择性。
Copper-Assisted Direct Nitration of Cyclic Ketones with Ceric Ammonium Nitrate for the Synthesis of Tertiary α-Nitro-α-substituted Scaffolds
作者:Zhi-Qiang Zhang、Tao Chen、Fu-Min Zhang
DOI:10.1021/acs.orglett.7b00040
日期:2017.3.3
An efficient and direct Cu-assisted nitrating approach to create synthetically valuable and challenging tertiary α-nitro-α-substituted moieties has been developed using cericammoniumnitrate as a nitrating reagent, oxidant, and Lewis acid. Notably, the commonly used clinical drug ketamine was smoothly synthesized in four steps.
A chemo- and regioselective α-hydroxylationreaction of carbonyl compounds with molecularoxygen as oxidant is reported. The hydroxylation reaction is catalyzed by a dinuclear Pd(II) complex, which functions as an oxygen transfer catalyst, reminiscent of an oxygenase. The development of this oxidation reaction was inspired by discovery and mechanism evaluation of previously unknown Pd(III)-Pd(III)
Diastereodivergent Catalytic Asymmetric Michael Addition of 2-Oxindoles to α,β-Unsaturated Ketones by Chiral Diamine Catalysts
作者:Yuan Wei、Shigang Wen、Zunwu Liu、Xinxin Wu、Bubing Zeng、Jinxing Ye
DOI:10.1021/acs.orglett.5b01149
日期:2015.6.5
catalytic asymmetric Michael addition of 2-oxindoles to α,β-unsaturated ketones has been successfully developed with two complementary chiral diamine catalysts, affording chiral 3,3-disubstituted oxindoles with two adjacent chiral centers. Diastereodivergence has been realized through modifying substrates and utilizing different catalysts. Either anti-or syn-configured products possessing vicinal quaternary