Electrophilic chemistry of propargylic alcohols in imidazolium ionic liquids: Propargylation of arenes and synthesis of propargylic ethers catalyzed by metallic triflates [Bi(OTf)3, Sc(OTf)3, Yb(OTf)3], TfOH, or B(C6F5)3
作者:Gopalakrishnan Aridoss、Viorel D. Sarca、James F. Ponder Jr、Jessica Crowe、Kenneth K. Laali
DOI:10.1039/c0ob00872a
日期:——
formed. Steric influence of the propargylic moiety on substrate selectivity is reflected in the lack of ortho propargylation for phenol and ethylbenzene by using propargylic alcohol Ia, and notable formation of the ortho isomer employing alcohol Ib. In the later case paraselectivity could be increased by running the reaction at r. t. for 10 h. The Bi(OTf)3-catalyzed reaction of 1,3-dimethoxybenzene with
(Cyclopentadienone)iron Shvo Complexes: Synthesis and Applications to Hydrogen Transfer Reactions
作者:Tarn C. Johnson、Guy J. Clarkson、Martin Wills
DOI:10.1021/om101101r
日期:2011.4.11
A series of (cyclopendienone)iron tricarbonylcomplexes were prepared using an intramolecular cyclization strategy. These were applied to the catalysis of the oxidation of alcohols to aldehydes and ketones. When paraformaldehyde was used as the hydrogen acceptor, formate esters were obtained as coproducts and, in several cases, the major products.
Synthesis of Planar Chiral Cobalt Metallocenes by Microwave-Assisted Diastereoselective Complexation
作者:Caroline J. Taylor、Majid Motevalli、Christopher J. Richards
DOI:10.1021/om060015r
日期:2006.5.1
Ether- and ester-linked diynes were readily synthesized in two steps by starting from secondary terminal propargylic alcohols. On either heat- or microwave-assisted reaction of the diynes with cyclopentadienylcobalt dicarbonyl, new planar chiral (η5-cyclopentadienone)(η5-cyclopentadienyl)cobalt metallocenes were formed with diastereomeric ratios of up to 5:1. For both the ether and ester series the