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The synthesis of ortho-substituted benzoic acid 3 from benzalphthalide 1 in the presence of ‘hydriodic acid—red phosphorus’ (HIaq/Pred) occurs via the formation of benzylphthalide 2 as reaction intermediate. Its preparation is optimized by use of the ‘supported reaction in dry media’ process (Silica/HIaq) under microwave irradiation for 8 min. The role of the red phosphorus in the reduction reaction is elucidated: it intervenes in a catalytic cycle by an oxido—reductive disproportionation with the liberated iodine, affording either hypophosphorous acid in aqueous media, or P2I4 in anhydrous media with concomitant regeneration of HI. Thus, the presence of Pred in the couple ‘HIaq/Pred’ allows recycling of the hydriodic acid and enhances its reducing efficiency.

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.

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 metallation reactions of the functionalized diphosphiranes 1a,b with the anionic metal transition complexes Na[(Cp)nM(CO)m] (M  Mo, W, or Co) afford σ- or π -diphosphaallyl complexes depending on the substituents of the intracyclic carbon atom. The same complexes are also obtained from their photochemical isomers, the 1,3-diphosphapropenes 2a,b. The complexes are thermally labile as shown by variable-temperature NMR spectroscopy. Upon heating, the σ-diphosphaallyl cobalt complex 3aC is irreversibly transformed into the π-complex 4aC. In contrast, with M  Fe and in toluene solution at reflux, reduced 1,3-diphosphapropenes 5a,b are obtained. Further, the gem-dihalogenated diphosphiranes 1c,d and their isomers 2c,d lead quantitatively to 1,3-diphosphaallene 6 under the same metallation conditions. The mechanism of the coordination reactions is discussed.

The metalation reactions of the functionalized diphosphiranes 1a–b with the anionic metal transition complexes (M = Mo, W, Co) afford the σ- or π- diphosphaallyl complexes (2 or 3, respectively) as function of the intracyclic carbon atom substituents. The thermal lability of these complexes is detected by variable-temperature NMR spectroscopy.

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.

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 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.

Phospholipids are the main components of biological membranes and the) spontaneously tend to self-assembly into liposomes. Synthetic double-chain so as bol amphiphiles allow the preparation of vesicles and can bc used as models of natural membranes and for preparing drug delivery systems. The formation of vesicles from single-chain perfluomalkylated phosphate or phosphoramidate amphiphiles war recently reported.1 We present the synthesis of new fluoroalkylatcd phosphinic acid amphiphiles bearing a P-C bond and an ionic polar head promoting self-organisation We have already described the synthesis of the phosphine derivatives by one-poireaction from red phosphorus via the in situ generation of PH3, and terminal alkenes and alkynes in basic media under sonication.2 We extend this reaction to perfluoroalkena under phase uansfert catalysis.

Pursuing our investigation into h e reactivity of red phosphorus. its hydrolysis derivatives (PH3, and H3,PO2).1,2 and P-H labile compounds? we report here a convenient method for the direct synthesis of free a-hydroxyalkyl phosphinic acid surfactants from aqueous hypophosphorous acid and the long-chain aldehydes or imincs under sonication.

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.

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).

The reaction of α-branched aldehydes with diethyl 1-carbomethoxyethyl phosphonate 1b in THF/nBuLi at low temperature leads stereoselectively to Z α-methyl α,β-unsaturated esters. From a linear aldehyde, the reaction is less stereoselective, while from α,β-unsaturated ones, the E isomers are predominantly formed in good yields. From diphenyl 1-carbomethoxyethyl phosphine oxide 2b, E α-methyl α,β-unsaturated esters are stereoselectively formed either in DMF/tBuOK or in phase transfer conditions, whatever the starting aldehyde is, also in good yields. This reagent can thus advantageously replace the corresponding P-ylid. In all cases, the reaction conditions are determined so that by-products formation is minimized.

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 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.