Selective Oxidation of Propargylic Alcohols into α,β-Acetylenic Aldehydes with a TiCl4/Et3N System
作者:Zhenfu Han、Hiroshi Shinokubo、Koichiro Oshima
DOI:10.1055/s-2001-16807
日期:——
A TiCl4/Et3N combination proved to be effective for the selective oxidation of propargylic alcohols into α,β-acetylenic aldehydes in good yields. Treatment of 2-hexyne-1,6-diol with TiCl4/Et3N provided 6-hydroxy-2-hexynal in good yield.
Benzannulation of Triynes to Generate Functionalized Arenes by Spontaneous Incorporation of Nucleophiles
作者:Rajdip Karmakar、Sang Young Yun、Jiajia Chen、Yuanzhi Xia、Daesung Lee
DOI:10.1002/anie.201412468
日期:2015.5.26
The thermal reaction of ester‐tethered 1,3,8‐triynes provides novel benzannulation products with concomitant incorporation of a nucleophile. Evidence suggests that this reaction proceeds via an allene‐enyne intermediate generated by an Alder‐ene reaction in the first step. Depending on the substituent of the alkyne moiety on the allene‐enyne intermediate, the subsequent transformation can take one
Direct Synthesis of α-Iodoenones by IPy<sub>2</sub>BF<sub>4</sub>-Promoted Rearrangement of Propargylic Esters
作者:Tatiana Suárez-Rodríguez、Ángel L. Suárez-Sobrino、Alfredo Ballesteros
DOI:10.1021/acs.joc.8b01746
日期:2018.10.19
A direct access to α-iodoeones from iodonium ion and propargylic tosylates or acetates is described. Bis(pyridine) iodonium tetrafluoroborate (IPy2BF4, Barluenga’s reagent) promotes the rearrangement of these propargylic alcohol derivatives in mild conditions. The transformation gives β-unsubstituted, β-monosubstituted, and β,β-disubstituted α-iodoenones in high yields. β-Substituted α-iodoenones are
Expedient Synthesis of <i>C</i><sub>3</sub>-Symmetric Hexasubstituted Benzenes via Nicholas Reaction/[2 + 2 + 2] Cycloaddition. New Platforms for Molecular Recognition
reaction from the starting dicobalt hexacarbonyl–propargylic complex. The macrocycles obtained were modified through [2 + 2 + 2] cycloaddition, generating two new C3-symmetric hexasubstituted benzene structures suitable for molecular recognition purposes.
Hydrogenation Promoter, Hydrogenation Catalyst, and Process for Producing Alkene Compound
申请人:Hori Junichi
公开号:US20080033221A1
公开(公告)日:2008-02-07
A hydrogenation promoter of the present invention is produced by reacting an alkyne compound or an alkene compound, a palladium compound represented by a general formula Pd(II)X
j
L
k
(where L represents a monodentate ligand or a polydendate ligand other than a phosphorus-containing ligand (when two or more Ls are present in the compound, the Ls may be the same or different), X represents an anionic group, j represents a value determined according to the valence of X so that X
j
has a valence of −2 as a whole, and k represents an integer in the range of 0 to 4), and a base in an organic solvent. Specifically, The hydrogenation promoter of the invention includes palladium nanoparticles containing the alkyne compound or the alkene compound as an agglomeration-preventing agent.