进行了钯催化的分子内串联环化反应,以合成致密的顺式/顺式稠合的氮杂四环结构。该过程涉及钯(II)催化的好氧aza-Wacker反应,然后是钯(0)催化的Heck反应。系统地研究了溶剂和苯的取代方式对一锅两步级联反应的影响,并提出了可能的机理。使用钯催化的aza-Wacker-Heck环化反应,也可以快速合成应变的五氢苯并[ f ]环戊基[ hi ]吲哚并嗪-6-和外消旋的γ-二十烷。
进行了钯催化的分子内串联环化反应,以合成致密的顺式/顺式稠合的氮杂四环结构。该过程涉及钯(II)催化的好氧aza-Wacker反应,然后是钯(0)催化的Heck反应。系统地研究了溶剂和苯的取代方式对一锅两步级联反应的影响,并提出了可能的机理。使用钯催化的aza-Wacker-Heck环化反应,也可以快速合成应变的五氢苯并[ f ]环戊基[ hi ]吲哚并嗪-6-和外消旋的γ-二十烷。
Palladium-Catalyzed Aerobic Oxidative Cyclization of Aliphatic Alkenyl Amides for the Construction of Pyrrolizidine and Indolizidine Derivatives
作者:Dan Yang、Kai-Yip Lo、Liu Ye
DOI:10.1055/s-0036-1588502
日期:2017.8
An efficient palladium-catalyzed aerobic oxidative cyclization has been developed to synthesize a variety of pyrrolizidine and indolizidine derivatives from simple aliphatic alkenyl amides in moderate to good yields. The reaction features the capability of accessing various N-heterocycles and the use of molecular oxygen (1 atm) as the green oxidant.
Palladium-Catalyzed Regioselective C–H Iodination of Unactivated Alkenes
作者:Benedikt S. Schreib、Erick M. Carreira
DOI:10.1021/jacs.9b03998
日期:2019.6.5
A palladium-catalyzedC-H iodination of unactivated alkenes is reported. A picolinamide directing group enables the regioselective functionalization of a wide array of olefins to furnish iodination products as single stereoisomers. Mechanistic investigations suggest the reversible formation of a six-membered alkenyl palladacycle intermediate through a turnover-limiting C-H activation.
Disclosed herein are compounds of formula (I) or pharmaceutical acceptable salts thereof,
wherein A, X
1
, X
2
, R
1
, R
2
, R
3
, m, n, and p are defined in the specification. Compositions including the compounds which can be useful for inhibiting Rho kinase (ROCK) and methods for using the compositions are also described.
induced by ultraviolet (UV) light. Forty-six examples with various functional groups are explored at room temperature with irradiation by three 26 W UV lamps (350–380 nm). The yield reaches 97%. The gram scale experiment product yield is 76%. Moreover, this system can be applied to the synthesis of several amino acid derivatives. Mechanistic studies show that benzoin is generated in situ from benzil under
OER for enhancing HER. The increased H2 production can be obtained at cathode; meanwhile, a variety of aromatic and aliphatic primary amines are selectively electrooxidized to nitriles with good yields at the anode. Mechanistic investigations suggest that NiII/NiIII may serve as the redox active species for the primary amines transformation. Hydrophobic nitrile products can readily escape from aqueous
对于电催化水分解,缓慢的阳极氧气逸出反应(OER)限制了阴极氢气逸出反应(HER)。因此,开发具有加速动力学的替代性阳极反应以生产特别是与HER结合的增值化学品非常重要。现在,据报道,NiSe纳米棒阵列在水中催化的热力学上更有利的伯胺(-CH 2 -NH 2)电氧化代替了OER以增强HER。可以在阴极获得增加的H 2生成量。同时,各种芳香族和脂肪族伯胺在阳极被选择性地电氧化成腈,并具有良好的收率。机理研究表明,Ni II / Ni III可以用作伯胺转化的氧化还原活性物质。疏水性腈产品可以很容易地从水电解质/电极界面逸出,避免了催化剂的失活,从而促进了连续的克级合成。