Oxidative Coupling Reaction of 1,3-diarylpropenes with Propane-1,3-dione Derivatives Mediated by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone with Molecular Oxygen
Photo-induced Decarboxylative Heck-Type Coupling of Unactivated Aliphatic Acids and Terminal Alkenes in the Absence of Sacrificial Hydrogen Acceptors
作者:Hui Cao、Heming Jiang、Hongyu Feng、Jeric Mun Chung Kwan、Xiaogang Liu、Jie Wu
DOI:10.1021/jacs.8b11218
日期:2018.11.28
boronates are among the most versatile building blocks that can be found in every sector of chemical science. We herein report a noble-metal-free method of accessing such olefins through a photo-induced decarboxylative Heck-type coupling using alkyl carboxylic acids, one of the most ubiquitous building blocks, as the feedstocks. This transformation was achieved in the absence of external oxidants through
1,2-二取代的烯烃,如乙烯基芳烃、乙烯基硅烷和乙烯基硼酸酯,是化学科学各个领域中最通用的结构单元。我们在此报告了一种无贵金属的方法,该方法使用烷基羧酸(最普遍的结构单元之一)作为原料,通过光诱导脱羧 Heck 型偶联获得此类烯烃。这种转变是在没有外部氧化剂的情况下通过有机光氧化还原催化剂和钴肟催化剂的协同组合实现的,H2 和 CO2 作为唯一的副产物。控制实验和 DFT 计算都支持基于自由基的机制,最终导致开发出脂肪族羧酸、丙烯酸酯和乙烯基芳烃的选择性三组分偶联。
Practical Iron-Catalyzed Allylations of Aryl Grignard Reagents
作者:Matthias Mayer、Waldemar M. Czaplik、Axel Jacobi von Wangelin
DOI:10.1002/adsc.201000228
日期:2010.9.10
reaction between aryl halides and allyl electrophiles has been developed. The underlying domino process exhibits high versatility with respect to the allylic leaving group (acetate, tosylate, diethyl phosphate, methyl carbonate, trimethylsilanolate, methanethiolate, chloride, bromide) and high economic and environmental sustainability with respect to the catalyst system (0.2–5 mol% tris(acetylacetonato)iron(III)
Asymmetric copper-catalyzed allylic alkylation between allyl bromides and alkyl Grignard reagents using a P-chiral monophosphorus ligand is described. A range of terminal olefins bearing tertiary or quaternary carbon centers were formed in good branched/linear selectivities and excellent enantioselectivities at copper loadings as low as 0.5 mol %.
Preparation of the 15-membered cycle (E,E,E)-1,6,11-tris[(2,4,6-triisopropylphenyl)sulfonyl]-1,6,11-triazacyclopentadeca3,8,13-triene (8) is reported. This cyclic triolefin forms a stable Pd0 complex 9 which catalyzes several cross-coupling reactions and can be recovered. Anchoring to a polystyrene framework affords a solid version of the catalyst, which is recovered by simple filtration and reused
Photochemical Heck benzylation of styrenes catalyzed by Na[FeCp(CO)2]
作者:Greyson W. Waldhart、Neal P. Mankad
DOI:10.1016/j.jorganchem.2014.12.033
日期:2015.9
Iron-catalyzed Heck coupling of benzyl chlorides and styrenes proceeds under photochemical conditions using the well-known anionic complex, [FeCp(CO)2]- (Fp−), as a catalyst. The reaction likely proceeds through the established SN2 mechanism for Fp− alkylation, followed by styrene migratory insertion and β-hydride elimination steps that are enabled by photochemical CO dissociation.