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The reaction of saturated and unsaturated organomagnesium compounds with the monohalogenated diphosphiranes, 1a - b , and their isomers, the 1,3-diphosphapropenes, 2a - b , leads to a series of substituted 1,3-diphosphapropenes and 1,3-diphosphadienes 4 - 8 ( a - b ), but with the dihalogeno-derivatives 1c - d and 2c - d , it gives quantitative yields of 1,3-diphospha-allene 9 . The reaction occurs via an anionic ring-opening involving an allylic anion intermediate 11a - b , detected by 31 P NMR.

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.

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.

The cis/trans stereochemistry of diphosphiranes 1a–g, 2a, and 2h is investigated by MNDO calculations in terms of substituent effects on intracyclic phosphorus and carbon atoms. This approach is co...

The aminolysis of the hexachlorocyclotriphosphazene, N3P3Cl6 1, by the oxodiamines H2N-(CH2)3-O(CH2)2-O-(CH2)3 NH2 2 and H2N-(CH2)3-O-(CH2)6-O-(CH2)3-NH2 3 occurs immediately and regiospecifically in dry media leading to the corresponding spiranic cryptands 4 and 5, respectively. This process is an actual improvement (time, selectivity and workup) on the standard reactions.

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.

The role of base catalysts (CsNaX zeolite, hydrotalcite, triethylamine and pyridine derivatives) upon the regioselectivity of the Pudovik reaction is studied. The unexpected synthesis of stable 1,2-dihydropyridine phosphonate derivatives via a one-pot addition reaction under mild conditions is described.

The cycloaddition reactions on Phosphorus Chemistry1 has allowed a new development of the three membered ring organophosphorus compounds. Starting from functionulized diphosphiranes obtained by action of carbenes on diphosphenes, we have studied their ring opening reactions leading to carbon insertion into P-P bond.

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.

Diphosphiranes 3a - 3f are obtained by action of diazo derivatives and carbenes on the trans-diphosphene 1 . The structures are elucidated by spectroscopic methods. In all cases the cycloaddition reaction is stereoselective.

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.

The synthesis of hybrid “metalloporphyrin-ellipticine” molecules is reported. These molecules are based on 9-methoxyellipticine and [5-(4-hydroxyphenyl)-10,15,20-tris (4-tolyl)]porphyrin linked by a ten-bond chain, −(CH2)4-CO-NH-(CH2)3−, between the hydroxyl group of the porphyrin and the pyridine nitrogen of the pyrido-carbazole. These molecules have been metallated with manganese, iron or zinc salts.