Oxidative Halo-Decarboxylation of .alpha.,.beta.-Unsaturated Carboxylic Acids
摘要:
A procedure for oxidative halo-decarboxylation of alpha,beta-unsaturated carboxylic acids using iodosylbenzene, or iodosylbenzene diacetate, and N-chloro-, N-bromo-, or N-iodosuccinimide is presented. Good yields of the corresponding bromoalkenes are obtained when the alpha,beta-unsaturated carboxylic acids are substituted with an aromatic substituent in the beta-position and N-bromosuccinimide is used as the halogenation reagent. The scope of mainly the oxidative bromo-decarboxylation reaction is presented, and a tentative mechanism is proposed.
Nucleophile-Selective Cross-Coupling Reactions with Vinyl and Alkynyl Bromides on a Dinucleophilic Aromatic Substrate
作者:Lu-Ying He、Mathias Schulz-Senft、Birk Thiedemann、Julian Linshoeft、Paul J. Gates、Anne Staubitz
DOI:10.1002/ejoc.201500138
日期:2015.4
A nucleophile-selective cross-coupling reaction on an aromatic compound bearing two metal groups, Bpin and SnMe3, has been developed. Previously, only aryl bromides and iodides could be used as electrophilic components, but in this work, the scope could be extended to vinyl and alkynyl bromides as electrophiles. This means that the roles typical in Sonogashira couplings or Heck reactions of the aromatic
4-<i>Endo</i>-<i>T</i><i>rig</i> Cyclization Processes Using Bis(collidine)bromine(I) Hexafluorophosphate as Reagent: Preparation of 2-Oxetanones, 2-Azetidinones, and Oxetanes
作者:Fadi Homsi、Gérard Rousseau
DOI:10.1021/jo9810361
日期:1999.1.1
Reaction in methylene chloride of bis(collidine)bromine(I) hexafluorophosphate with alpha,beta-unsaturated acids and alpha,beta-unsaturated N-sulfonamides was found to lead diastereospecifically to the corresponding 2-oxetanones and 2-azetidinones in moderate yields (23-60%), by an almost unknown 4-endo cyclization. This process allow the synthesis of these interesting classes of products in one step
CuI-Catalyzed Cross-Coupling
Reaction of (<i>E</i>)-Vinyl Bromides with
Nitrogen-Containing Heterocycles
作者:Jincheng Mao、Qiongqiong Hua、Jun Guo、Daqing Shi、Shunjun Ji
DOI:10.1055/s-2008-1077955
日期:——
An efficient and straightforward copper-catalyzed method allowing vinylation of N-nucleophiles with various substituted (E)-vinyl bromides under palladium-free and ligand-free conditions has taken a high yield (up to 95%). Noteworthy is that the double-bond geometry of these vinyl halides was retained with our protocol.
Visible light-mediated metal-free double bond deuteration of substituted phenylalkenes
作者:Roman Iakovenko、Jan Hlaváč
DOI:10.1039/d0gc03081c
日期:——
Photoactivated metal free deuteration of a double bond was developed in an environmentally friendly manner.
双键的光活化金属无氘化反应以环境友好的方式进行了开发。
Hydrodebromination of allylic and benzylic bromides with water catalyzed by a rhodium porphyrin complex
作者:Wu Yang、Chen Chen、Kin Shing Chan
DOI:10.1039/c8dt02168f
日期:——
complex catalyst using water as the hydrogen source without a sacrificial reductant. Mechanistic investigations suggest that bromine atomabstraction via a rhodium porphyrin metalloradical operates to give the rhodium porphyrin alkyl species and the subsequent hydrolysis of the rhodium porphyrin alkyl species to a hydrocarbon product is a key step to harness the hydrogenfrom water.