Combined dealkoxycarbonylation and lactonisation of unsaturated malonates in ionic liquids
摘要:
Heating unsaturated malonates with LiCl and water in [bmim][Br] or [bmim][BF4]/[bmim][Br] produces unsaturated esters or lactones, respectively. (c) 2005 Elsevier Ltd. All rights reserved.
Dual Photoredox and Gold Catalysis: Intermolecular Multicomponent Oxyarylation of Alkenes
作者:Matthew N. Hopkinson、Basudev Sahoo、Frank Glorius
DOI:10.1002/adsc.201400580
日期:2014.9.15
developed using a dual gold and photoredoxcatalytic system. Inexpensive organic dyes could be employed as the photocatalyst using aryldiazonium salts, while the combination of gold and iridium catalysts allowed for diaryliodonium compounds to be employed as the source of the arene coupling partner. In both cases, α‐arylated ether products were generated under remarkably mild conditions using readily accessible
FeCl<sub>3</sub>-Catalyzed Regio-Divergent Carbosulfenylation of Unactivated Alkenes: Construction of a Medium-Sized Ring
作者:Leiyang Lv、Zhiping Li
DOI:10.1021/acs.joc.8b01621
日期:2018.9.21
carbosulfenylation of unactivated alkenes with electrophilic N-sulfenophthalimides has been developed. This protocol provides a straightforward and efficient access to various medium-sized rings, especially strained 7- and 8-membered carborings with a sulfur atom attached. The endo/exo selectivity in the reaction depends on the atom number of the chain between arene and alkene. Broad substrate scope, high
Air-tolerant C–C bond formation via organometallic ruthenium catalysis: diverse catalytic pathways involving (C5Me5)Ru or (C5H5)Ru are robust to molecular oxygen
carbon pronucleophiles, various [2+2+2] cycloadditions, and addition of a diazocompound to an alkyne are shown to proceed in the presence of air. Notably diverse catalytic manifolds remain supported under conditions generally regarded as prohibitive. Building on rare reports from the literature we show that a range of organometallic transformations based on reaction intermediates derived from (C5Me5)Ru
碳原子亲核试剂的钌催化取代,各种[2 + 2 + 2]环加成反应以及重氮化合物向炔烃的加成反应均在空气存在下进行。值得注意的是,各种催化歧管在通常被认为是禁止的条件下仍保持支撑。基于文献的稀有报道,我们表明基于衍生自(C 5 Me 5)Ru或(C 5 H 5)Ru部分的反应中间体的一系列有机金属转化是与空气相容的。
Diastereoselective Carbocyclization of 1,6‐Heptadienes Triggered by Rhodium‐Catalyzed Activation of an Olefinic CH Bond
作者:Christophe Aïssa、Kelvin Y. T. Ho、Daniel J. Tetlow、María Pin‐Nó
DOI:10.1002/anie.201400080
日期:2014.4.14
studied. Reported herein is the rhodium(I)‐catalyzed rearrangement of prochiral 1,6‐heptadienes into [2,2,1]‐cycloheptane derivatives with concomitant creation of at least three stereogenic centers and complete diastereocontrol. Deuterium‐labeling studies and the isolation of a key intermediate are consistent with a group‐directedCHbondactivation, followed by two consecutive migratory insertions
使用α,ω-二烯作为烯属碳氢键的官能化试剂的研究很少。本文报道了铑(I)催化的前手性1,6-庚二烯重排为[2,2,1]-环庚烷衍生物,同时产生至少三个立体中心和完整的非对映控制。氘标记研究和关键中间体的分离与基团定向的 C H 键激活,然后是两个连续的迁移插入一致,只有后一步是非对映选择性的。
Isomerization of Olefins Triggered by Rhodium-Catalyzed CH Bond Activation: Control of Endocyclic β-Hydrogen Elimination
作者:Stephanie Y. Y. Yip、Christophe Aïssa
DOI:10.1002/anie.201500596
日期:2015.6.1
Five‐membered metallacycles are typically reluctant to undergo endocyclic β‐hydrogen elimination. The rhodium‐catalyzed isomerization of 4‐pentenals into 3‐pentenals occurs through this elementary step and cleavage of two CH bonds, as supported by deuterium‐labeling studies. The reaction proceeds without decarbonylation, leads to trans olefins exclusively, and tolerates other olefins normally prone