77100-93-7Relevant academic research and scientific papers
Synthesis of Hf(IV) complex from cyclam (1,4,8,11-tetraazacyclotetradecane) -containing amino-amido groups
Thirumavalavan, Munusamy,Lee, Jiunn-Fwu
, p. 223 - 226 (2012)
The reactivity of cyclam (1,4,8,11-tetraazacyclcotetradecane)-containing amino-amido groups with hafnium(IV) chloride was described. Taylor & Francis Group, LLC.
Redox-active alkylsulfones as precursors for alkyl radicals under photoredox catalysis
Patel, Sandeep,Paul, Biprajit,Paul, Hrishikesh,Shankhdhar, Rajat,Chatterjee, Indranil
, p. 4857 - 4860 (2022/04/19)
A method for generating alkyl radicals using visible-light photoredox catalysis is described. This procedure was found to present an efficient means to access a diverse collection of 1°, 2°, and 3° alkyl radicals through the single-electron transfer of sulfones under mild reaction conditions. These alkyl radicals generated via the reductive desulfonylation of readily synthesized and stable alkylsulfones were engaged to forge C-C bonds. A detailed study was also carried out to shed light on the mechanism.
Electrochemical Tandem Olefination and Hydrogenation Reaction with Ammonia
Zhang, Xiaofeng,Jiang, Runze,Cheng, Xu
, p. 16016 - 16025 (2021/08/24)
An electrochemical Horner-Wadsworth-Emmons/hydrogenation tandem reaction was achieved using ammonia as electron and proton donors. The reaction could give two-carbon-elongated ester and nitrile from aldehyde or ketones directly. This reaction could proceed with a catalytic amount of base or even without a base. The ammonia provides both the electron and proton for this tandem reaction and enables the catalyst-free hydrogenation of an α,β-unsaturated HWE intermediate. More than 40 examples were reported, and functional groups, including heterocycles and hydroxyl, were tolerated.
ZWITTERIONIC CATALYSTS FOR (TRANS)ESTERIFICATION: APPLICATION IN FLUOROINDOLE-DERIVATIVES AND BIODIESEL SYNTHESIS
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Paragraph 0019; 0031, (2021/01/29)
An amide/iminium zwitterion catalyst has a catalyst pocket size that promotes transesterification and dehydrative esterification. The amide/iminium zwitterions are easily prepared by reacting aziridines with aminopyridines. The reaction can be applied a wide variety of esterification processes including the large-scale synthesis of biodiesel. The amide/iminium zwitterions allow the avoidance of strongly basic or acidic condition and avoidance of metal contamination in the products. Reactions are carried out at ambient or only modestly elevated temperatures. The amide/iminium zwitterion catalyst is easily recycled and reactions proceed in high to quantitative yields.
Visible-light induced metal-free cascade Wittig/hydroalkylation reactions
Miao, Pannan,Li, Ruining,Lin, Xianfeng,Rao, Liangming,Sun, Zhankui
supporting information, p. 1638 - 1641 (2021/03/09)
Cascade reactions are green and powerful transformations for building multiple carbon-carbon bonds in one step. Through a relay olefination and radical addition process, we were able to develop the cascade Wittig/hydroalkylation reactions induced by visible light. This metal-free radical approach features mild conditions, robustness, and excellent functionality compatibility. It allows access to saturated C3 homologation products directly from aldehydes or ketones. The synthetic utility of this method is demonstrated by a two-step synthesis ofindolizidine 209D.
A metal-free iodine-mediated conversion of hydroxamates to esters
Ghosh, Subhankar,Banerjee, Jeet,Ghosh, Rajat,Chattopadhyay, Shital K.
, p. 1353 - 1360 (2020/03/30)
A metal-, oxidant-, and additive-free conversion of hydroxamates to esters have been achieved using molecular iodine as the reagent using a novel but not-so-explored heron-type rearrangement. The reaction proceeds with almost equal facility with substrates having either electron-donating or electron-withdrawing substituent. Similarly, α,?-unsaturated, and sterically hindered ortho-substituted hydroxamates also undergo the desired transformation smoothly.
Radical-Mediated Strategies for the Functionalization of Alkenes with Diazo Compounds
Su, Yong-Liang,Liu, Geng-Xin,Liu, Jun-Wen,Tram, Linh,Qiu, Huang,Doyle, Michael P.
supporting information, p. 13846 - 13855 (2020/09/21)
One of the most common reactions of diazo compounds with alkenes is cyclopropanation, which occurs through metal carbene or free carbene intermediates. Alternative functionalization of alkenes with diazo compounds is limited, and a methodology for the addition of the elements of Z-CHR2 (with Z = H or heteroatom, and CHR2 originates from N2 CR2) across a carbon-carbon double bond has not been reported. Here we report a novel reaction of diazo compounds utilizing a radical-mediated addition strategy to achieve difunctionalization of diverse alkenes. Diazo compounds are transformed to carbon radicals with a photocatalyst or an iron catalyst through PCET processes. The carbon radical selectively adds to diverse alkenes, delivering new carbon radical species, and then forms products through hydroalkylation by thiol-assisted hydrogen atom transfer (HAT), or forms azidoalkylation products through an iron catalytic cycle. These two processes are highly complementary, proceed under mild reaction conditions, and show high functional group tolerance. Furthermore, both transformations are successfully performed on a gram-scale, and diverse γ-amino esters, γ-amino alcohols, and complex spirolactams are easily prepared with commercially available reagents. Mechanistic studies reveal the plausible pathways that link the two processes and explain the unique advantages of each.
Oxo-Rhenium-Catalyzed Radical Addition of Benzylic Alcohols to Olefins
Bandari, Chandrasekhar,Nicholas, Kenneth M.
, p. 3320 - 3327 (2020/03/23)
Although carbon radicals generated from a variety of alcohol derivatives have proven valuable in coupling and addition reactions, the direct use of alcohols as synthetically useful radical sources is less known. In this report, benzylic alcohols are shown to be effective radical precursors for addition reactions to alkenes when treated with triphenylphosphine or piperidine with the catalyst ReIO2(PPh3)2 (I).
Amide/Iminium Zwitterionic Catalysts for (Trans)esterification: Application in Biodiesel Synthesis
Lam, Ying-Pong,Ng, Wing-Hin,Tan, Fei,Tse, Ying-Lung Steve,Wang, Xinyan,Yeung, Ying-Yeung
, p. 8083 - 8092 (2019/08/26)
A class of zwitterionic organocatalysts based on an amide anion/iminium cation charge pair has been developed. The zwitterions are easily prepared by reacting aziridines with aminopyridines. They are catalytically applicable to transesterifications and dehydrative esterifications. Mechanistic studies reveal that the amide anion and iminium cation work synergistically in activating the reaction partners, with the iminium cationic moiety interacting with the carbonyl substrates through nonclassical hydrogen bonding. The reaction can be applied to large-scale synthesis of biodiesel under mild conditions.
Visible-light-initiated manganese-catalyzed Giese addition of unactivated alkyl iodides to electron-poor olefins
Dong, Jianyang,Wang, Xiaochen,Wang, Zhen,Song, Hongjian,Liu, Yuxiu,Wang, Qingmin
supporting information, p. 11707 - 11710 (2019/10/02)
Herein, we report a mild protocol for direct visible-light-initiated Giese addition of unactivated alkyl iodides to electron-poor olefins (Michael acceptors) with catalysis by decacarbonyl dimanganese, Mn2(CO)10, an inexpensive earth-abundant-metal catalyst. This protocol is compatible with a wide array of sensitive functional groups and has a broad substrate scope with regard to both the alkyl iodide and the Michael acceptor.
