Chhan Siv

Palladium catalysed allylic acetoxylation of dialkyl allyl phosphonates.

Abstract The catalytic acetoxylation of dialkyl allyl phosphonates with the Pd(OAc)2/benzoquinone/MnO2/HOAc system leads, regioselectively, to dialkyl 3- acetoxy 1-alkenyl phosphonates. On the basis of the regio- and stereoselectivity of the reaction, a mechanism is proposed which involves a (π-allyl) palladium complex as intermediate.

Synthèse de phosphinites dérivés de sucres : applications en cyclodimérisation du penta 2,4-diénoate de méthyle, en hydrogénation et en hydrosilylation de la pentolactone

Abstract Sugar-derived phosphinites, when used as ligands in the catalytic hydrogenation of α-ketopentolactone, lead to the corresponding alcohol with a better enantiomeric excess (20%) than in hydrosilylation (10%). In the cyclodimerisation of penta-2,4-dienoic acid methyl ester they lead to the meso cycloocta-3,7-diene-1,2-doic dimethyl ester.

Synthese de ligands de type amino-diphosphinites; etude en RMN 13C et 31P. Application a la dimerisation du butadiene par les complexes du nickel

Abstract The new chiral aminodiphosphinite ligands are readily prepared from chiral amino acids. These compounds were characterized by 13 C and 31 P NMR spectroscopy and their behaviour as homogeneous catalysts was investigated in the linear dimerization of butadiene.

Asymmetric telomerization of buta-1,3-diene with a pair of different telogens

Abstract Telomerization of buta-1,3-diene can be carried out simultaneously with two different telogens. In the example we report, one of them in nucleophilic (isopropanol), whereas the other is electrophilic (paraformaldehyde).