Gerard Mignani

A straightforward synthesis of unsymmetrical secondary phosphine boranes

A one-pot procedure for the synthesis of unsymmetrical alkyl-substituted secondary phosphine oxides is described. The sequential addition of N-benzylaniline to a solution of dichlorophenylphosphine and 1-methylimidazole in methylcyclohexane, separating of the protic ionic liquid formed, addition of Grignard reagent followed by hydrolysis gave unsymmetrical secondary phosphine oxides (SPOs) in high yield. The use of ionic liquids in the first step is essential and streamlined the synthesis. Unsymmetrical SPOs could be quantitatively reduced to secondary phosphine using a catalytic amount of Ti(OiPr)4 and tetramethyldisiloxane (TMDS) under mild reaction conditions.

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. Cyclization of prochiral radicals proceeded with varying stereochemical outcomes, depending on the size of the incoming radical. 2-Pyridyl and 2-quinolyl radicals led to biaryl compounds, which result from attack onto the ortho position of the arylsulfinate rather than a thiophilic substitution.

Second generation N-heterocyclic carbene–Pt(0) complexes as efficient catalysts for the hydrosilylation of alkenes

A new class of benzimidazolylidene carbene-Pt(0) complexes was developed and used to efficiently catalyse the hydrosilylation of alkenes.

Anionic ring-opening polymerization of cyclic organosiloxanes using phosphorus ylides as strong non-ionic bases

Abstract Phosphonium alcoholates obtained by treatment of dimethylmethylene-[tris(dimethylamino)]phosphorane ( 1 ) with an excess of alcohol polymerize cyclic siloxanes (D 4 ) at room temperature. The thermal lability of this system permits simplifies polymer purification.

Efficient and Convenient Method for the Synthesis of N‐Arylhydrazones using a Palladium‐Catalyzed Bond‐Forming Reaction

Abstract A highly effective, convenient, and reproducible industrial process for palladium‐catalyzed carbon–nitrogen cross coupling has been developed and applied on a large scale. Thus various functionalized N‐arylhydrazones have been easily prepared and well characterized by conventional spectroscopic methods.

Poly-Functionalization of Polysiloxanes: New Industrial Opportunities

Polysiloxanes containing grafted and/or end-capped functional groups, due to their specific properties, receive attention in various industrial ap plications. This paper presents the synthesis and development of new poly functional silicones. For example, the grafting of selected organofunctional groups onto silicone backbones allows us to increase the hydrophobic-oleophobic perma nence or hydrophilic softness properties for textile treatments. To achieve these properties, new synthetic routes using novel organometallic catalysts and specific monomers have been developed.