Reductive Coupling of Allylic Esters with Carbonyl Compounds Mediated by the Mischmetall/[SmI2/Pd0cat.′]cat. System
作者:Sédami Médégan、Florence Hélion、Jean-Louis Namy
DOI:10.1002/ejoc.200500291
日期:2005.11
“two-stage catalysis” has been carried out using SmI2 and Pd(PPh3)4 in catalytic amounts together with mischmetall (an alloy of the light lanthanides) as a co-reductant. A catalytic scheme that takes into account previously reported reactions of SmI2/Pd0cat. and mischmetall/SmI2,cat. systems is proposed. It has also been shown that palladium complexes catalyse the addition of organolanthanide species
Stereoselective Modification of <i>N</i>-(α-Hydroxyacyl)-glycinesters via Palladium-Catalyzed Allylic Alkylation
作者:Alexander Horn、Uli Kazmaier
DOI:10.1021/acs.orglett.9b01497
日期:2019.6.21
excellent nucleophiles in Pd-catalyzed allylic alkylation. The method allows for the stereoselective introduction of a wide range of side chains, including highly functionalized ones. Both diastereomers can be accessed through variation of the reaction conditions. Furthermore, the use of stannylated carbonates introduces vinylstannane motifs, which are eligible for subsequent C–C coupling reactions.
Tandem Palladium and Isothiourea Relay Catalysis: Enantioselective Synthesis of α-Amino Acid Derivatives via Allylic Amination and [2,3]-Sigmatropic Rearrangement
作者:Stéphanie S. M. Spoehrle、Thomas H. West、James E. Taylor、Alexandra M. Z. Slawin、Andrew D. Smith
DOI:10.1021/jacs.7b05619
日期:2017.8.30
has been developed for the enantioselective synthesis of α-aminoacid derivatives containing two stereogenic centers from readily accessible N,N-disubstituted glycine aryl esters and allylic phosphates. The optimized process uses a bench-stable succinimide-based Pd precatalyst (FurCat) to promote Pd-catalyzed allylic ammonium salt generation from the allylic phosphate and the glycine aryl ester. Subsequent
Highly Stereoselective Cobalt-Catalyzed Allylation of Functionalized Diarylzinc Reagents
作者:Paul Knochel、Guillaume Dunet
DOI:10.1055/s-2007-980344
日期:2007.6
Functionalized diarylzinc reagents react readily with allylic chlorides or phosphates in the presence of Co(acac)2 (10 mol%) to give the SN2 products in high yields and with retention of the double-bond configuration. Functionalities like ester, ketone, or cyano are tolerated.
The catalytic allylic difluoromethylation of allyl carbonates with (difluoromethyl)zinc reagent, which can be readily prepared via iodine-zinc exchange reaction of difluoroiodomethane with diethylzinc, was achieved by employing copper salt as a catalyst. The difluoromethylation proceeded with not only good-to-high yields but also complete regioselectivity. Furthermore, the reaction was demonstrated