Synthesis and derivatization of highly-functionalized λ⁵-phospholes.

A variety of λ(5)-phosphole derivatives bearing up to three distinct peripheral functionalities have been prepared by regiospecific [3+2] cycloaddition reactions of the diphosphinoketenimine (PPh2)2C=C=NtBu (1) with electron-poor alkenes. Selective derivatization of the exocyclic functional groups, including formation of dimetallic complexes with a phosphole core, was subsequently accomplished.

A three-component reaction involving isocyanide, phosphine and ketenimine functionalities.

A three-component reaction involving diphosphinoketenimines, isocyanides and water or ethanol leading to the formation of new five-membered azaphosphaheterocycles is described.

Synthesis and reactivity of diphosphine metal complexes bearing peripheral ketenimine functionalities.

Diphosphinoketenimine ligands (PPh(2))(2)C=C=NR (1a R = (t)Bu, 1b R = Ph) were reacted with different Cu(I), Ag(I), Au(I), Pd(II), Ru(II) and Mo(0) metal complexes bearing weakly coordinating ligands yielding a number of mono-, di-, and trimetallic species with the diphosphine acting as either chelate or bridging ligand. The reactivity of some of the new complexes toward water and MeLi was investigated. The mononuclear Pd(II) complex [PdCl(2){(PPh(2))(2)C=C=NPh}] (6b) is transformed into the diphosphinoamide complex [PdCl(2){(PPh(2))(2)CHC(=O)(NHPh)}] (12) by nucleophilic addition of water.

New approach to sulfonated diphosphine complexes: synthesis and amphoteric behaviour of zwitterionic [Mn+(CO4{(PPh2)2C(H)SO3-}].

Oxidation of the thioketone residue in the complex [Mn(CO)4{(PPh2)2C=S}]+ (2) with hydrogen peroxide affords the sulfonate derivative [Mn(CO)4{(PPh2)2C(H)SO3}] (3), which shows amphoteric behaviour in reversible acid-base processes, and is easily chlorinated to give [Mn(CO)4{(PPh2)2C(Cl)SO3}] (8).

Generation of N-heterocyclic carbenes by metal-mediated coupling of propargylamine and isocyanides.

A new method for the synthesis of heterocyclic carbenes of imidazol-2-ylidene and oxazol-2-ylidene types implying a cycloaddition reaction of propargylamine and propargylic alcohol, respectively, to coordinated isocyanide ligands has been developed.