General Method for the Palladium-Catalyzed Allylation of Aliphatic Alcohols
作者:Anthony R. Haight、Eric J. Stoner、Matthew J. Peterson、Vandana K. Grover
DOI:10.1021/jo0301907
日期:2003.10.1
A palladium catalysis-mediated approach to coupling aliphaticalcohols with allyl carbonates has been developed. The method allows for the allylation of primary, secondary, and tertiary alcohols efficiently under mild conditions. Limitations were explored as well as the asymmetric application of the chemistry. Regiochemical and olefin geometry was controlled in the coupling of unsymmetrical allylating
Contemporaneous Dual Catalysis by Coupling Highly Transient Nucleophilic and Electrophilic Intermediates Generated in Situ
作者:Barry M. Trost、Xinjun Luan
DOI:10.1021/ja110501v
日期:2011.2.16
contemporaneous dualcatalysis, that selectively couples two highly reactive catalytic intermediates while overcoming competing trapping by stoichiometric reactive species also present in the reaction. The reaction proceeds via the convergence of a vanadium-catalyzed propargylic rearrangement and a palladium-catalyzedallylicalkylation. It generates a variety of α-allylated α,β-unsaturatedketones, which are
Simple phosphinite–oxazoline ligands for asymmetric catalysis
作者:Geraint Jones、Christopher J Richards
DOI:10.1016/s0040-4039(01)01041-3
日期:2001.8
4-(Hydroxymethyl)oxazolines, derived from (S)-serine methyl ester and a variety of acid chlorides (RCOCl), were reacted with Ph2PCl to give new phosphinite-oxazoline P-N ligands. These mediate the palladium catalysed asymmetric alkylation with dimethyl malonate with the following racemic propenyl substrates (RCH)-C-1=CHCH(OX)R-1: (a) R-1 =Ph, X = Ac-96% e.e.(S) with R=Ph; (b) R-1 = Me, X = CO2' Bu-70% e.e.(S) with R=(eta (5)-C5H4)(eta (4)-C4Ph4)CO. (C) 2001 Published by Elsevier Science Ltd.
A Diosphenol-Based Strategy for the Total Synthesis of (−)-Terpestacin
作者:Barry M. Trost、Guangbin Dong、Jennifer A. Vance
DOI:10.1021/ja070571s
日期:2007.4.1
A novel diosphenol-based strategy has been developed for the enantioselective synthesis of (-)-terpestacin by multiple usage of the alpha-diketone functionality, first in the "Pd AAA-Claisen rearrangement" protocol, and second by the employment of its oxidized form, the ene-1,2-dione, as an excellent Michael acceptor. This synthesis demonstrates that the sequence of O-allylation-Claisen rearrangement provides a chemo- and regioselective enolate allylation, which can be performed asymmetrically with respect to the enolate or allyl fragment or both. In addition, many interesting chemoselectivity issues, including a highly selective RCM and a dihydroxylation, have been addressed. Overall, this synthesis was accomplished in 20 longest linear steps (24 total steps) from the inexpensive and commercially available 3-methyl-1,2-cyclopentanedione.