Search

New phosphorous catanionic amphiphiles were easily prepared by an acid−base reaction between (α-hydroxyalkyl)-phosphinic or -phosphonic acid and cethyltrimethylammonium hydroxide. In this way, we obtained, in nearly quantitative yields, bicatenary phosphinates and bicatenary and tricatenary phosphonates. The aggregation properties of these new catanionic amphiphiles were investigated at low concentrations in water (ranging from 1 to 5 mM), focusing in particular on spontaneous formation of different aggregate morphologies (vesicles, ribbons, tubules). Light and electron microscopy was used to identify the aggregate morphology of the catanionic amphiphiles. Moreover, these catanionic amphiphiles were able to organize into ordered lyotropic mesophases in concentrated water solutions, visualized by optical polarizing microscopy. Finally, the phosphorous catanionic amphiphiles, without rigid cores, were unexpectedly found to show thermotropic liquid-crystalline behavior. The various thermotropic mesophases we...

We have studied the surfactant properties of a series of single- and double-chain (a-aminoalkyl)-phosphonocarboxylic- and (a-aminoalkyl)-phosphonic acid amphiphiles, prepared in nearly quantitative yields by one-pot selective hydrolysis of the mixture obtained by reacting P-H bond tetraoxyspirophosphorane and long-chain aldimines. Disodium salts of monocatenary derivatives are soluble in water and the cmc's were determined by tensiometry, showing surfactant properties for all compounds. Thermodynamic calculations confirmed the tensiometry results, in the sense that phosphonocarboxylates present much more electrostatic destabilizing repulsions favoring micellization less than phosphonates. The disodium salts of these phosphonic acids were able to organize into ordered lyotropic mesophases in concentrated water solutions, visualized by optical polarizing microscopy. The nature of the observed mesophases seems to be strongly dependent on the polar head structure. All compounds were studied using the Langmuir technique. The more hydrophobic derivatives formed stable monolayers versus time at the air/water interface. The areas occupied per molecule depend on the polar head structure and the number of alkyl chains. The conformations at the air/water interface were estimated by a molecular modeling study.

New double-chain bis-(α-hydroxyalkyl)phosphinic acids 1 are synthesized from NaH 2 PO 2 .H 2 O and aliphatic aldehydes. Direct and quantitative one-pot synthesis of new 4-alkoxybenzaldehydes 2 is realized from 1-bromoalkanesand 4-hydroxybenzaldehyde. Addition of NaH 2 PO 2 .H 2 O to aldehydes 2 leads to the formation of the bis-adducts and also to the cleavage of the ether bond. New [α-hydroxy-(4-alkoxybenzyl)]phosphinic acids 3 are prepared by addition of aldehydes 2 to aqueous hypophosphorous acid.

A new series of (α-hydroxyalkyl)phosphinic acids 1 was prepared in good yields from long-chain aldehydes (C8−C18) and 50% aqueous hypophosphorous acid under sonication. Oxidation of these phosphinic acids by dimethyl sulfoxide in the presence of catalytic amounts of iodine afforded the corresponding (α-hydroxyalkyl)phosphonic acids 2. Critical micelle concentrations (cmc) of the amphiphilic monocaternary (α-hydroxyalkyl)phosphorus acid ammonium salts 1 and 2, determined by tensiometry and 31P NMR, showed a good correlation between the two methods and indicated their high surfactant properties. The phosphonate salts 2 with two dissociable groups had much higher cmc values than those of the corresponding phosphinate analogues 1. The ammonium salts of these phosphorus acids were able to form ordered lyotropic mesophases in concentrated water solutions, visualized by optical polarization microscopy. The nature of the observed mesophases (hexagonal or lamellar) depended on the concentration, the temperature, t...

The reactivity of red phosphorus towards aldehydes was investigated under basic and acidic media. It was demonstrated that the real phosphorylating agent involved in the reaction was phosphane (PH3) in basic media, and hypophosphorous acid (H3PO2) in acidic media. A convenient one-pot synthesis of (α-hydroxyalkyl)phosphinic acids from red phosphorus and aldehydes in basic media was realized under sonication. The same reaction under acidic media in the presence of hydriodic acid led to the corresponding phosphonic acids. The (α-hydroxyalkyl)phosphinic acids were readily prepared under sonication from hypophosphorous acid and aldehydes in the presence of catalytic amounts of hydrochloric acid. The mechanism of the addition reaction of PH3 to benzaldehyde was elucidated and shows the complexity of the reaction as a function of the experimental conditions.

In the diphosphirane series, the substitution of one aryl group (2,4,6-tri-tert-butyl‐phenyl) by a chlorine atom leading to the trans P‐chloro-diphosphirane via the cis isomer intermediate can be readily realized in chlorinated solvent under sonication or in the presence of gaseous hydrogen chloride in diethyl ether at room temperature.

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.

Ultrasound irradiation enhances the rate and improves the yield of the heterogeneous asymmetric Michael reaction without any modification of the enantioselectivity with respect to standard procedure. These improvements are assigned to ultrasonic mechanical effects.

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.

In order to evaluate the biological properties of new α-aminophosphonic acids 4a-g bearing a pyrrolic or thiophenic moiety, their synthesis via the corresponding esters 3a-g is carried out by two methods. The standard procedure leading to α-aminophosphonic esters 3 in good yields, requires heating of the neat reactants for several days. The sonochemical activation improves substantially the rate of formation of 3 and promotes the yields of the reaction. The rate enhancement for this homogeneous sonochemical reaction depends upon the temperature, the nature of the solvent, and the structure of the imine

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.

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 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 completed by calculations of dipole moments. These results are compared to experimental dipole moment measurements of the synthesized diphosphiranes 3a–f.

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 structure of the functionalized trans-diphosphiranes 1a-e, obtained by reaction of halogenocarbenes with the trans-diphosphene is confirmed by X-ray diffraction. The photolysis of 1a-e lead to the functionalized cis- and trans-1,3-diphosphapropenes 2a-e as major products, via the diphosphiranyl and the diphosphapropenyl radical intermediates. The latter are characterized by ESR spectroscopy using the spin-trap method. The trans configuration of 2a is also confirmed by X-ray diffraction. The mechanism of the ring-opening, involving P-P bond rupture, is discussed

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.

Chiral P-H spirophosphoranes reacted with long-chain prochiral aldimines and, after selective hydrolysis, afforded (alpha-amino)phosphonic acid amphiphiles in both enantiopure forms.

Direct synthesis of free (alpha-hydroxyalkyl)phosphinic acid amphiphiles 1 can be readily realized by sonication of the heterogeneous mixture of 50% aqueous hypophosphorous acid and long-chain aldehydes in the presence of catalytic amounts of hydrochloric acid. Oxidation of these phosphinic acids by DMSO in the presence of catalytic amounts of iodine quantitatively leads to the corresponding phosphonic acids 3. IR spectra of the phosphinic acids 1 in the condensed phase and in solution reveal the presence of intra- and intermolecular associations. Dissociation constants of the phosphorus acids 1 and 3 determined by potentiometric and (31)P NMR titrations show a good correlation between the two methods. The phosphinic acid amphiphiles 1 are slightly stronger than the corresponding phosphonic acids 3. (alpha-Hydroxyalkyl)phosphonium chlorides are prepared in good yields from the phosphine PH(3) and long-chain aldehydes in acidic media.

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.

La reaction de reduction-oxydation appliquee a des composes organomercuriques hetero-cycliques oxygenes permet la fonctionnalisation de ces heterocycles. Des alcools tetrahydro-furfuryliques sont ainsi obtenus. It has been possible to functionalize heterocyclic organomercuric compounds by an oxidation reduction reaction. Tetrahydrofurfuryl alcohols have been obtained.

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.

This paper deals with the synthesis of N α -(β-naphthylsulfonylaminoglycyl)-argininamide compounds and the results of a pharmacological study ( in vitro and in vivo ). No thrombin inhibition was obtained with N α -arylsulfonyl-aminoalkyl-(4-amidinophenyl)-alaninamide compounds in which the 4-amidinophenylalanyl residue was substituted by an arginyl residue.

The Wittig-Horner reaction from diethyl cyanomethyl phosphonate 1a and aldehydes is seldom highly stereoselective1. The use of diiscpropyl cyanomethyl phosphonate 1b has been recently proposed to improve the stereoselectivity of the reaction towards the E-α, β- unsatured nitriles 2E2.

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.