allowing for the conversion of β,γ-unsaturatedcarboxylicacids into allylic hydrazides via radical regioselective allylic decarboxylative amination is reported. The coexistence of the copper catalyst is essential for the high yield and regioselectivity. A new cooperative organophotoredox/copper catalysis allowing for the conversion of β,γ-unsaturatedcarboxylicacids into allylic hydrazides via radical regioselective
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。
Enantiodivergent and γ-Selective Asymmetric Allylic Amination
作者:Jianmin Wang、Jie Chen、Choon Wee Kee、Choon-Hong Tan
DOI:10.1002/anie.201107317
日期:2012.3.5
judicious choice of the double bond geometry of the the β,γ‐unsaturated carbonyl compound. Computational studies reveal the possible origin of the inversed enantioselectivity, and the potential for enantiodivergent synthesis chiral amine‐containing substrates is attractive.
pyrazoleamides and a chiral N, N'-dioxide-nickel(II) complex catalyst enables a highly enantioselective Doyle-Kirmse reaction. The pyrazoleamide substituent serves as both an activating and a directing group for the ready formation of a metal-carbene- and Lewis-acid-bonded ylide intermediate in the assistance of a dual-tasking nickel(II) complex. An alternative chiral Lewis-acid-bonded ylide pathway
尽管使用经典的手性 Rh(II) 和 Cu(I) 催化剂证明锍叶立德的 [2,3]-σ 重排的高对映选择性(Doyle-Kirmse 反应)令人惊讶地难以捉摸,但原则上这是由于难以精细区分硫的异位孤对和锍叶立德硫的手性反转。在这里,我们展示了新的 α-重氮吡唑酰胺和手性 N, N'-二氧化镍 (II) 配合物催化剂的协同合并能够实现高度对映选择性的 Doyle-Kirmse 反应。吡唑酰胺取代基作为活化基团和导向基团,在双任务镍 (II) 配合物的帮助下,很容易形成金属-卡宾和路易斯酸键合的叶立德中间体。即使对于对称二烯丙基硫烷的反应,另一种手性路易斯酸键合的叶立德途径也大大提高了产物的对映纯度。在一系列芳基或乙烯基取代的 α-重氮吡唑胺和硫化物上进行的大多数转化都进行得很快(大多数情况下在 5-20 分钟内),结果非常好(收率高达 99%,ee 高达 96%),提供了一个突破在对映选择性