Ketone Synthesis by a Nickel-Catalyzed Dehydrogenative Cross-Coupling of Primary Alcohols
作者:Thomas Verheyen、Lars van Turnhout、Jaya Kishore Vandavasi、Eric S. Isbrandt、Wim M. De Borggraeve、Stephen G. Newman
DOI:10.1021/jacs.9b03280
日期:2019.5.1
intermolecular coupling of primaryalcohols and organotriflates has been developed to provide ketones by the action of a Ni(0) catalyst. This oxidative transformation is proposed to occur by the union of three distinct catalytic cycles. Two competitive oxidation processes generate aldehyde in situ via hydrogentransfer oxidation or (pseudo)dehalogenation pathways. As aldehyde forms, a Ni-catalyzed carbonyl-Heck
Selective Catalytic Synthesis of α-Alkylated Ketones and β-Disubstituted Ketones via Acceptorless Dehydrogenative Cross-Coupling of Alcohols
作者:Dipanjan Bhattacharyya、Bikash Kumar Sarmah、Sekhar Nandi、Hemant Kumar Srivastava、Animesh Das
DOI:10.1021/acs.orglett.0c04098
日期:2021.2.5
phosphine-free pincer ruthenium(III) catalyzed β-alkylation of secondaryalcohols with primary alcohols to α-alkylated ketones and two different secondaryalcohols to β-branched ketones are reported. Notably, this transformation is environmentally benign and atom efficient with H2O and H2 gas as the only byproducts. The protocol is extended to gram-scale reaction and for functionalization of complex vitamin E
Direct conversion of secondary propargyl alcohols into 1,3-di-arylpropanone <i>via</i> DBU promoted redox isomerization and palladium assisted chemoselective hydrogenation in a single pot operation
作者:Rimpa De、S. Antony Savarimuthu、Shubhadeep Chandra、Mrinal K. Bera
DOI:10.1039/d1nj02972j
日期:——
Palladium(II)acetate is found to be an efficient catalyst for the single-step conversion of secondary propargyl alcohols to 1,3-diarylpropanone derivatives under mild basic conditions. The reaction is believed to proceed via redox isomerisation of secondary propargyl alcohols followed by chemoselective reduction of an enone double bond with formic acid as an adequate hydrogen donor. A large number
发现乙酸钯 ( II ) 是一种有效的催化剂,可在温和的碱性条件下将仲炔醇一步转化为 1,3-二芳基丙酮衍生物。据信,该反应通过仲炔丙醇的氧化还原异构化,然后用甲酸作为适当的氢供体对烯酮双键进行化学选择性还原而进行。大量的 1,3-二芳基丙酮衍生物可以很容易地从毫克级到几克级制备。
Photoredox-Catalyzed Hydroacylation of Olefins Employing Carboxylic Acids and Hydrosilanes
hydroacylation reaction of alkenes has been achieved employing readily available carboxylicacids as the acyl source and hydrosilanes as a hydrogen source via photoredox catalysis. The combination of both single electron transfer and hydrogen atom transfer steps has dramatically expanded new applications of carboxylicacids in organic synthesis. The protocol also features extremely mild conditions, broad
Base promoted <i>gem</i>-difluoroolefination of alkyl triflones
作者:Ren-Yin Yang、Hui Wang、Bo Xu
DOI:10.1039/d1cc01132d
日期:——
A new synthesis of gem-difluoroalkenes from readily available alkyl triflones and difluorocarbene precursors such as TMSCF2Br has been reported. The reaction, regardless of electronic effect, gives gem-difluoroalkenes in good to excellent yields. The mechanism may involve deprotonation of triflones, nucleophilic addition, and the elimination of SO2CF3.