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The bis-allylic 1 and the bis-propargylic 6 derivatives react with the zirconocene “ZrCp2” and lead, after electrophilic addition, to the corresponding chiral trans heterocyclopentanes (MSi,Ge,P) 3–5 and bis-methylenecyclopentanes 8. New chiral diphosphine 9 is obtained starting from the intermediate complex 2 or the functionalized heterocyclopentane 4.

The generation of phosphine PH 3 by alkaline hydrolysis of red phosphorus is realized. The subsequent alkylation of PH 3 by terminal alkenes and alkynes in basic media leading to the corresponding aliphatic and vinylic phosphine derivatives can occur by two-steps or one-pot reaction by a Michael-like reaction mechanism.

Sonication improves substantially the rate of formation of diphosphene 1 with respect to standard procedures. The cyclopropanation of 1 using sonochemical generation of methylene or halogeno-carbenes constitutes an interesting alternative in the diphosphirane synthesis. Furthermore, ultrasonic effects in a chlorinated solvent allow the first substitution of a diphosphirane without ring-opening.

In the diphosphirane serie, whereas the fragmentation is a side reaction during the photochemical, thermal or cationic ring opening, the oxidation of the phosphorus lone pairs leads quantitatively to the corresponding phosphaalkenes, and the unstable phosphinidene.

The synthesis, with asymmetric induction, of chiral hexacovalent phosphorus anions, allows a polarimetric kinetic study of epimerization or racemization mechanism of these compounds which is shown to be irregular (acid catalyzed).

We have prepared phosphite ozonides 1b – 3b which are efficient and clean singlet oxygene generators at low temperature.

Resume A compound has been isolated whose elemental analysis, nmr and IR data are consistent with an equilibrium phosphoranide phosphite.

We have obtained phosphorus ozonides ( 3b , 4b and 5b ) in which phosphorus atom is hexacoordinated. In solution, these adducts are more stable than pentacovalent phosphorus homologs (ΔC* = 23 kcal.mole−1 for 4b )

The functionalized diphosphiranes 1 a–c, in presence of Lewis acid, undergo two kinds of reaction:the ring opening leading to the phosphenium-phosphonium ion 2a–c obtained according to an electrocyclic reaction and the fragmentation giving phosphaalkene 3a–c and phosphonium ion 4. The deprotonation reaction of 2a–c in hexane leads to phosphino-phosphaalkenes 6a–c.

The 3,3-dihalogeno-1,2-diphosphiranes 1(a–b) and its photochemical isomers, the 2,3-dihalogeno-diphosphapropenes 8(a–b) lead to the 1,3-diphosphaallene 4 by action the methyllithium. The anionic ring opening mechanism appears most likely.