Cationic Ruthenium Catalysts for Alkyne Annulations with Oximes by C–H/N–O Functionalizations
摘要:
Cationic ruthenium(II) complexes enabled efficient redox-neutral annulations of alkynes with readily available oximes. The catalytic dehydrative C-H/N-O bond functionalization proved to be broadly applicable and was shown to proceed through a reversible cyclometalation.
Use of functionalized onium salts as a soluble support for organic synthesis
申请人:Vaultier Michel
公开号:US20070043234A1
公开(公告)日:2007-02-22
The invention relates to the use of a onium salt functionalized by at least one organic function, as a soluble support, in the presence of at least one organic solvent, for organic synthesis of a molecule, in a homogenous phase, by at least one transformation of said organic function. The onium salt enables the synthesized molecule to be released. The onium salt is present in liquid or solid form at room temperature and corresponds to formula A
1
+
, X
1
−
, wherein A
1
+
represents a cation and X
1
−
represents an anion.
Rhodium(III)-Catalyzed Redox-Neutral CH Annulation of Arylnitrones and Alkynes for the Synthesis of Indole Derivatives
作者:Zhi Zhou、Guixia Liu、Yan Chen、Xiyan Lu
DOI:10.1002/adsc.201500580
日期:2015.9.14
By using a nitrone as the oxidizingdirectinggroup, a mild, practical and efficient rhodium(III)‐catalyzed CH functionalization for the synthesis of indole derivatives has been developed. This reaction obviates the need for an external oxidant and shows good functional group tolerance. The employment of a sterically hindered Mes group on the carbon center of the nitrone is crucial to produce indoles
Electroremovable Traceless Hydrazides for Cobalt-Catalyzed Electro-Oxidative C–H/N–H Activation with Internal Alkynes
作者:Ruhuai Mei、Nicolas Sauermann、João C. A. Oliveira、Lutz Ackermann
DOI:10.1021/jacs.8b03521
日期:2018.6.27
studies provided strong support for a facile C-H cobaltation by an initially formed cobalt(III) catalyst. The subsequent alkyne migratory insertion was interrogated by mass spectrometry and DFT calculations, providing strong support for a facile C-H activation and the formation of a key seven-membered cobalta(III) cycle in a regioselective fashion. Key to success for the unprecedented use of internal
as a powerful strategy for organometallic catalysis, and yet electrocatalytic C−Hactivation is restricted to strongly N‐coordinating directing groups. The first example of electrocatalytic C−Hactivation by weak O‐coordination is presented, in which a versatileruthenium(II) carboxylate catalyst enables electrooxidative C−H/O−H functionalization for alkyne annulations in the absence of metal oxidants;
电催化已被认为是有机金属催化的有力策略,但是电催化CH活化仅限于强N配位的导向基团。给出了通过弱O配位进行电催化C-H活化的第一个例子,其中通用的羧酸钌(II)催化剂可在没有金属氧化剂的情况下实现炔烃环化的电氧化C / H / OH功能化。从而利用可持续的电力作为唯一的氧化剂。机械学的见解为简便的有机金属CH钌钌化和关键钌(0)中间体的有效电化学再氧化提供了有力的支持。
Regio- and Stereoselective Synthesis of Enol Carboxylate, Phosphate, and Sulfonate Esters via Iodo(III)functionalization of Alkynes
synthesized through regio- and stereoselective iodo(III)functionalization of alkynes. The combination of chlorobenziodoxole and silver salt has proven to generate a versatile cationic iodine(III) electrophile to activate alkynes and engage various carboxylic acids, triethyl phosphate, and p-toluenesulfonic acid as nucleophiles. The β-iodo(III)enol esters serve as starting materials for the synthesis of multisubstituted