DBU-Catalyzed Rearrangement of Secondary Propargylic Alcohols: An Efficient and Cost-Effective Route to Chalcone Derivatives
作者:Mrinal K. Bera、Rimpa De、Antony Savarimuthu、Tamal Ballav、Pijush Singh、Jayanta Nanda、Avantika Hasija、Deepak Chopra
DOI:10.1055/s-0040-1707909
日期:2020.10
A 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU)-catalyzed rearrangement of diarylated secondarypropargylic alcohols to give α,β-unsaturated carbonyl compounds has been developed. The typical 1,3-transposition of oxy functionality, characteristic of Mayer–Schuster rearrangements, is not observed in this case. A broad substrate scope, functional-group tolerance, operational simplicity, complete atom economy
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。
Modular Synthesis of Furans with up to Four Different Substituents by a
<i>trans</i>
‐Carboboration Strategy
作者:Hongming Jin、Alois Fürstner
DOI:10.1002/anie.202005560
日期:2020.8.3
on treatment with MHMDS (M=Na, K), B2(pin)2, an acid chloride and a palladium/copper co‐catalyst system, undergo a reaction cascade comprised of trans‐diboration, regioselective acylation, cyclization and dehydration to give trisubstituted furylboronic acid pinacol ester derivatives in good yields; subsequent Suzuki coupling allows a fourth substituent of choice to be introduced and hence tetrasubstituted
A facile, copper-catalyzed aminoarylation reaction of various aryl/alkyl alkynes was realized by utilizing N-fluoroarylsulfonimides (NFSI) as aminoarylation or amination reagent with hydroxyl as directing group. With this methodology, various α,β-unsaturated carbonyl compounds and indenones were efficiently constructed, and the synthetic application for indole derivatives was also provided. The aminoarylation
Regioselective Access to Structurally Diverse Coumarin Analogues through Iron-Catalysed Annulation Reactions
作者:Qiao Ren、Jie Kang、Muyao Li、Lujiang Yuan、Ruoyun Chen、Lei Wang
DOI:10.1002/ejoc.201700999
日期:2017.10.10
A highly efficient iron-catalysed propargylation/alkyne oxacyclization/isomerization strategy is described. Biologically active furo[3,2-c]coumarins and pyrano[3,2-c]coumarins are expeditiously assembled with high regioselectivities.
描述了一种高效的铁催化的炔丙基化/炔基羰基化/异构化策略。具有高区域选择性的生物活性呋喃[3,2- c ]香豆素和吡喃并[3,2- c ]香豆素被迅速组装。