Didier Bouyssi

FUNCTIONALIZED ACETYLENES AS VERSATILE BUILDING-BLOCKS FOR THE MULTICOMPONENT ASSEMBLING OF POLYSUBSTITUTED FURANS AND PYRROLES

- This review highlights the versatility of functionalized alkynes in the multicomponent construction of polysubstituted furan and pyrrole derivatives.

A Novel Palladium Catalyst for Cross‐Coupling of Allyl Acetates with Arylboronic Acids

The palladium-catalyzed coupling reactions of various arylboronic acids and allylic acetates take place readily under mild conditions. The choice of ligand in the palladium catalyst and the solvent are critical to the yields of coupled products.(© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)

Palladium-Catalyzed C(sp2)−H Alkylation of Aldehyde-Derived Hydrazones with Functionalized Difluoromethyl Bromides

A palladium-catalyzed C(sp(2))-H difluoromethylation of aldehyde-derived hydrazones using bromodifluoromethylated compounds to afford the corresponding functionalized difluoromethylketone hydrazones has been established. It is proposed that a radical/SET mechanism proceeding via a difluoroalkyl radical may be involved in the catalytic cycle. Applications of the methodology to the synthesis of α,α-difluoro-β-ketoesters and α,α-difluoroketones (RCOCF2 H) have been illustrated.

Copper-Catalyzed β-Trifluoromethylation of Conjugated Hydrazones

The Cu-catalyzed direct β-trifluoromethylation of α,β-unsaturated aldehyde N,N-dibenzylhydrazones with Togni hypervalent iodine reagent is described. The reaction yields stereodefined CF3-alkenyl derivatives under mild conditions and is proposed to proceed via a radical process.

Palladium-mediated cascade or multicomponent reactions: A new route to carbo- and heterocyclic compounds

In recent years, new processes based on transition-metal-mediated intramolecular addition reaction of heteronucleophiles and stabilized carbon nucleophiles to unactivated alkenes and alkynes have been developed in our laboratory. In this article, we summarize a number of recent synthetic applications of these new processes. Emphasis is placed on the development of multicomponent reactions based on a Pd-mediated intramolecular cyclization coupled with a carbon-carbon bond-forming reaction. Applications of this methodology to the synthesis of natural lignans are also reported.

Amines as key building blocks in Pd-assisted multicomponent processes

Summary In the last few years, palladium-mediated three-component synthesis has emerged as an important synthetic methodology to gain access to nitrogen-containing structures. The latest developments in this area are discussed in this review.

New developments in the Pd-catalysed cyclisation-coupling reaction of alkene-containing carbonucleophiles with organic halides (and triflates). The first examples of asymmetric catalysis.

Abstract The results of our preliminary investigations directed toward asymmetric catalysis of the cyclocarbopalladation of alkenes bearing a proximate nucleophile with organic halides (or triflates) are disclosed. A series of bidentate phosphine ligands were evaluated in intramolecular versions of this reaction using ( E )-2-[7-(2-bromophenyl)-hept-4-enyl]-malonic acid dimethyl ester ( 1 ) and ( Z )-2-[7-(2-trifluoromethanesulfonyloxy-phenyl)-hept-4-enyl]-malonic acid dimethyl ester ( 9 ) as model substrates. The highest enantioselective induction was obtained with aryl triflate 9 which produced the corresponding cyclopentylindane as a single diastereomer in 54% chemical yield and 43% ee by using PdCl 2 [ S -(−)-TolBINAP] as chiral catalyst and K 2 CO 3 as base.

Ruthenium-Catalyzed Tandem C–H Fluoromethylation/Cyclization of N-Alkylhydrazones with CBr3F: Access to 4-Fluoropyrazoles

4-Fluoropyrazoles are accessible in a single step from readily available aldehyde-derived N-alkylhydrazones through double C-H fluoroalkylation with tribromofluoromethane (CBr3F). RuCl2(PPh3)3 has been proven to be the most efficient catalyst for this transformation when compared to a range of other Cu-, Pd-, or Fe-based catalyst systems.

1.08 – One or More CC Bond(s) Formed by Addition: Addition of Carbon Radicals and Electrocyclic Additions to CC Multiple Bonds

This review covers from 1995 to 2003 the field of carbon radical and electrocyclic additions to carboncarbon multiple bonds as a complement to the original review by A. J. Clark and P. C. Taylor ( ).

Sequential Michael addition/biscyclization reactions leading to the formation of highly substituted polycyclic substrates: some preliminary studies

An intermolecular Michael addition reaction of a malonate or malononitrile to unsaturated carbonyl substrates Z2a, E2a and E2b followed by a palladium-mediated biscyclization reaction led to the formation of highly functionalised tricyclic compounds with, in general, a high level of selectivity. A preliminary study on the transformation of one of these resulting substrates into a tetracyclic compound is also presented.