Pd/C-catalyzed room-temperature hydrodehalogenation of aryl halides with hydrazine hydrochloride

Treatment of aryl and heteroaryl halides with catalytic amounts of Pd/C in the presence of hydrazine hydrochloride in basic medium (sodium hydroxide or sodium t-butylate) at room temperature leads to the corresponding hydrodehalogenation products with high selectivity. Aryl iodides, bromides, chlorides and fluorides can be reduced using this reagent combination. The reduction is compatible with various electron-donating or electron-withdrawing groups.     

Synthetic Applications of Phosphonium Diylides

Abstract

Phosphonium diylides 1 react with electrophiles leading to new monoylides which permit., by a Wittig reaction, the E stereoselective synthesis of various di- or tri-substituted α,β-unsaturated functionalized compounds.     

New Cyclotriphosphazenes with P-CAr Bonds

Abstract

We describe some new cyclotriphosphazenes in which the phosphorus substituents are either free rotating aromatic or heteroaromatic groups, or rigid spirobiaryl units.     

New Applications of the Lithiated Phosphinimine Ph3P=N-Li: Synthesis of α,β-Unsaturated Nitriles and P=N-P Linked Phosphinimines

Abstract

The reaction of Ph₃P-N-Li⁽¹²⁾ with various α,β-unsaturated esters gives access to new N-(α,β-unsaturated acyl) phosphinimines. which can undergo intramolecular aza-Wittig reaction (at 65 - 110°C) to afford the corresponding nitriles.     

New Applications of Ph 3 P=N--Li in Organic Synthesis and Heteroatom Chemistry

The lithium triphenylaminophosphonium azayldiide 1 proved again to be a very good tool in organic synthesis, allowing further synthesis of various compounds such as vinyl nitriles, aromatic or heteroaromatic nitriles, and mono-, bis-, and trisphosphinimines.     

Diastereoselective Michael addition of 2H-2-oxo-1,4,2-oxaza phosphinanes to olefins

Diastereoselective Michael additions of 2-hydrogeno-2-oxo-1,4,2-oxazaphosphinanes to olefins were described. Phosphinopeptide compounds were obtained in very good yield (up to 90%) and diasteromeric excesses ranging from 26 to 78%.     

Unexpected Rearrangement of Diethyl (±)(S,S)-1,2-epoxy-2-Phenylpentylphosphonate by NH 3(aqu.) : An Easy Entry to Ethyl 1-Formyl-1-Phenylbutylphosphonate

A simple reaction of diethyl ( - )(S,S)-1,2-epoxy-2-phenylpentylphosphonate with 28% NH 3(aqu.) in MeOH led to the ethyl 1-formyl-1-phenylbutylphosphonate in excellent yield. The procedure consists simply in stirring the substrate and 28% NH 3(aqu.) in MeOH, at 40;C.     

A Stepwise Synthesis of Diversified Phosphazene Oligomers

Abstract

A stepwise approach to oligophosphazenes in which substituents at each phosphorus of the backbone can be diversified is described, through new N-chloroaminophosphorus compounds. Heterophosphazenes have also been obtained.     

Synthesis of New Phosphomycin Analogues

Abstract

In the aim to carry out a quantitative reactivity/structure/biological activity relationship, a general four step synthesis, gives us access to a number of new phosphomycin analogues. A new synthesis of di- and tri-substituted vinylphosphonates via cuprate reactions and their epoxidation by dioxirane are described.