Ph. Coutrot

5-formyl-δ—valerolactone : A useful synthon for the chiral synthesis of the vespa orientalis pheromone and the mosquito oviposition attractant pheromone

A synthetic scheme starting from the reaction between the lithiated N-allyl-N-methyl-(bisdimethylamino)phosphoramide anion and the triflate derivative of (R)-(-)- or (S)-(+)-2,3-O-isopropylideneglycerol is described to prepare the key chiral synthon (R)-5- or (S)-5-formyl-δ-valerolactone that leads to the title compounds.

A new synthesis of 3-deoxy-d-manno-2-octulosonic acid (KDO)

Abstract A KDO synthesis is described using in the key step a potassic anion derived from isopropyl dichloro or dibromoacetate, as an efficient equivalent to install an α-ketoester unit onto a conveniently protected D-mannose.

2-Diethoxyphosphoryl alcanoic acid dianions (lithium α-lithiocarboxylates): IV. A direct route to 2-fluoro-2-alkenoic acids by the Horner synthesis. Application in the field of pyrethroids

Abstract 2-Diethoxyphosphoryl-2-fluoroacetic acid was converted into the lithium α lithiocarboxylate dianion by treatment with n-butyllithium in hexane/tetrahydrofuran at −70°C. The Horner reaction between this new dianion and carbonyl compounds gave various 2-fluoro-2-alkenoic acids. Application of the method to the cis,trans caronaldehyde ethyl esters led to the 2-fluoroethenyl pyrethroid derivatives (Z,cis, E-cis, Z-trans, E-trans).

Synthese de peptides modifies incorporant un motif phosphore n ou c terminal

Abstract A general route to phosphopeptids with a 2-oxoalkylphosphonate moiety at the terminal N-aminogroup or with a 1-aminoalkylphosphonate moiety at the terminal C-carboxyl group is described. The method allows the preparation of various phosphopeptids with an α-alkylated carbon atom on the P-C bond from the very available dialkylphosphonoalcanoic acids as starting products. Phosphopeptides with a2-oxoalkylphosphonate moiety as terminal N-aminogroup or 1-aminoalkylphosphonate moiety as terminal C-carbonyl group are prepared from the same dialkylphosphono-alcanoic acids as starting products.

Hydrometallation d'alcynes en presence de derives de cuivre(I)

Abstract Reagents prepared from diisobutylalane (dibal) or tributylstannane and copper(I) species hydrometallate terminal alkynes in a syn way.

Synthèse de précurseurs d'analogues d'états de transition de réactions enzymatiques de transcarbamylation

Abstract A one pot synthesis in five steps of immediate precursors of new transition state analogues of enzymatic transcarbamylation reactions, N-[(phosphinylmethyl)phosphonate]-L-aspartate and N-[(phosphinylmethyl)phosphonate]-L-ornithine is described.

Synthèse dérivés insaturés d'acides α-aminés précurseurs de pseudoglycopeptides

Abstract The reaction between lithiated anions derived from N-substituted (diethyl-β-ketophosphono)-α-aminoacids and aldehyde compouds gives direct access to unsaturated derivatives of α-aminoacids. Application to the glucidic serie leads to an attractive route to pseudoglycopeptide precursors.

Synthèse générale de β-cétophosphonates α-fluorés précurseurs d'énones α-fluorées, application en série pyréthrénique

Abstract Dialkylphosphonofluoracetylchlorides are used to introduce directly the 2-oxophosphonate 1-fluorinated synthons on organometallic reagents. A Horner reaction of the 3 derivated anions with aldehydes gave various 2-fluoro-2-enones. Application to the cis, trans caronaldehyde ethyl esters led to the 2-fluoroethenyl pyrethroid derivatives.

SYNTHÈSE ET ÉTUDE COMPARÉE DES PROPRIÉTÉS COMPLEXANTES DE DÉRIVÉS DE L'ACIDE METHYLÈNE DIPHOSPHONIQUE

Abstract Two original acid derivatives of methylene diphosphonic acid (MDP) with two inequivalent phosphorus atoms have been synthesised: [(thiophosphonato)-methyl]phosphonic acid, (MDPS), and [(isopropyiamido phosphonato)-methyl] phosphonic acid, (MDPN). A poten- tiometric study allowed to define the stoechiometry of the complex formed between MDP and magnesium (II) in alcaline medium and a 31P NMR study proved the dissymetric structure of this MDPMg2+ complex. The displacement of the coordination equilibrium between Black Eriochrome T and magnesium (II) permitted to compare the coordination strength of MDP, MDPS and MDPN with the cation Mg2+.

NOUVELLES PETITES MOLÉCULES HAUTEMENT FONCTIONNALISÉES : PRÉPARATION D'ÉPOXYPHOSPHONATES α-CHLORÉS. ÉTUDE DE LEUR TRANSFORMATION EN α-CÉTOPHOSPHONATES β-HALOGÉNÉS

Abstract A range of α-chlorinated epoxyphosphonates has been prepared by epoxydation of α-halo-genated vinylphosphonates with an excess of MCPBA. The thermal rearrangement and the reactions of these new phosphonates with magnesium halides that lead to β-halogeno α-keto-phosphonates are described.