Relay-Heck Cross-Coupling Between Alkenyl Halides and Unsaturated Alcohols in the Synthesis of Open-Chain Analogues of Musk Odorant Vulcanolide.

Unactivated alkenyl iodides and bromides underwent an unprecedented palladium-catalyzed relay-Heck cross-coupling with a whole range of alkenols of different chain lengths linking the alkene and the alcohol, affording unsaturated aldehydes and ketones in moderate to good yields. In contrast, alkenyl triflates were not suitable partners for this reaction. This method allowed the preparation of open-chain analogues of the musk odorant Vulcanolide, several of which retained key olfactory properties of the parent molecule.

Intramolecular homolytic substitution of sulfinates and sulfinamides.

A general and efficient method for the synthesis of cyclic sulfinates and sulfinamides based on intramolecular homolytic substitution (S(H)i) at the sulfur atom by aryl or alkyl radicals is described. Both alkyl and benzofused compounds can be accessed directly from easily prepared acyclic precursors. Enantiomerically enriched sulfur-based heterocycles were formed through an S(H)i process with inversion of configuration at the sulfur atom.

Platinum dichloride-catalyzed cycloisomerization of ene-ynamides.

[reaction: see text] Various ene-tosylynamides react with platinum(II) chloride and lead to bicyclic nitrogenated heterocycles. This unprecedented and easily operated process can be coupled with a hydrolysis of the intermediate cyclic tosylenamides in a one-pot transformation, which provides cyclobutanones.

Molecular mobility of confined phases in model mesoporous (MCM-41) and microporous (AlPO(4)-5 zeolite) host materials.

The considered host materials are well suited to confine quasi-(1d) molecular phases, seeing that their porosities are composed of parallel unconnected cylindrical pores. For such a simple geometry, confinement effects can be simply described by a single parameter, the pore diameter phi. Our study concerns medium and ultra confinement ranges ( 40 A >or= Ø >or= 7.

[Role of IgE in the study of the allergic risk of the young child (author's transl)].

Cord blood IgE were determined by using the PRIST and the RAST techniques in 123 cases. The RAST assay was never positive. Total IgE were detectable in 34% of the samples; statistically increased levels were found in babies born from allergic mothers and/or when the mothers were treated with progesterone during their gestation.