Abstract: Novel bis(dialkylamide) compounds having the formula: R2R3NOC—R1a—CONR4R5 are particularly useful solvents, for example in plant-protection formulations.

Abstract: The invention relates to silicon oils, more particularly, to a novel method for the preparation of a silicon oil by polymerization and rearrangement of cyclic siloxanes in the presence of an alkaline catalyst and a co-catalyst which is a cryptand (macroheterobicyclic diamine) acting as a polymerization accelerator.

Abstract: Novel bis(dialkylamide) compounds having the formula: R2R3NOC—R1a—CONR4R5 are particularly useful solvents, for example in plant-protection formulations.

Abstract: The invention relates to silicon oils, more particularly, to a novel method for the preparation of a silicon oil by polymerization and rearrangement of cyclic siloxanes in the presence of an alkaline catalyst and a co-catalyst which is a cryptand (macroheterobicyclic diamine) acting as a polymerization accelerator.

Abstract: This invention relates to a method for preparing taxane derivatives of general formula (I) by esterification at a temperature between −10 and 60° C. of a derivative of baccatine III or 10-deacetyl baccatine III of general formula (II) by means of an acid of general formula (III), followed by replacement of the protective groupings G1, G2 and R2 of the resulting product by hydrogen atoms. In formulae (I), (II) or (III), Ar stands for an aryl radical; R stands for hydrogen or acetyl; R1 is benzoyl or ter.butoxycarbonyl; G1 is a hydroxy function protective grouping, G2 stands for the acetyl radical or a hydroxy function protective grouping, and R2 stands for a hydroxy function protective grouping.

Abstract: The invention relates to a nucleophilic reagent which is useful for grafting a substituted difluoromethyl group onto a compound containing at least one electrophilic function, or for the synthesis of oxysulphide-containing and fluorine-containing organic derivatives, wherein said reagent comprises: a) a fluorocarboxylic acid of formula Ew—CF2—COOH where Ew represents an electron-withdrawing atom or group, at least partially salified with an organic or inorganic cation, and b) a polar aprotic solvent; and in that the content of releasable protons carried by its various components, including their impurities, is at most equal to half the initial molar concentration of the said fluorocarboxylic acid. A synthetic process uses this reagent by heating in order to graft a substituted difluoromethyl group onto various compounds.

Abstract: The invention relates to a nucleophilic reagent which is useful for grafting a substituted difluoromethyl group onto a compound containing at least one electrophilic function, or for the synthesis of oxysulphide-containing and fluorine-containing organic derivatives, wherein said reagent comprises:

Abstract: Provided is a process for grafting a substituted difluoromethyl group onto a compound bearing at least one electrophilic substituent, comprising (i) contacting the compound bearing at least one electrophilic substituent with a nucleophilic reagent which comprises (a) a fluorocarboxylic acid having the formula Ea—CF2—COOH, wherein Ea is an electron-withdrawing atom or group, the fluorocarboxylic acid being at least partially salified with an organic or inorganic cation and (b) a polar aprotic solvent, and (ii) exposing the resulting medium of reaction to the action of microwave energy.

Abstract: The invention involves a procedure for synthesizing aryl hydrazine through reduction of a diazo derivative. The distinguishing feature of the method is that it involves at least the following step: c) bringing a diazo derivative into contact with a sulphite solution in which the pH level is at least 7. Applications: organic synthesis.

Abstract: A compound of the formula I: ##STR1## wherein Ar represents an aryl radical;R.sub.1 represents a hydrogen atom, an aroyl radical, or a radical of the formula R.sub.4 --O--CO;R.sub.2 and R.sub.3 together form a 5- or 6-membered saturated heterocycle;G.sub.1 represents an acetyl radical or a protecting group of the hydroxyl functional group; andG.sub.2 represents a protecting group of the hydroxyl functional group.

Abstract: The present invention relates to compounds composed essentially of a linear, cyclic or branched polyorganosiloxane having, per molecule, at least 3 siloxy units, including at least one siloxy functional unit of formula: ##STR1## where R.sup.1 represents a C.sub.1 to C.sub.4 alkyl or phenyl radical, X contains an N,N'-di- and/or trisubstituted phenylenediamine functional group, bonded to the silicon via an Si-(hydrocarbon linking unit)-N and/or Si-(hydrocarbon linking unit)-C bond, and a is a number chosen from 0, 1 and 2. The present invention also relates to the use of such compounds as antiozonants for rubbers and in particular for rubber compositions for tires.

Abstract: This invention relates to a method of preparing taxane derivatives of general formula (I) by esterification of protected baccatine III or 10-deacetylbaccatine III by means of an acid of general formula (VII), elimination of protection groupings of the ester obtained, and acylation of the amine function of the side chain. In formulae (I) and (VII): Ar stands for aryl, R is hydrogen or acetyl, R.sub.1 is benzoyl or R.sub.2 -CO--O- in which R.sub.2 is alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, bicycloalkyl, phenyl or heterocyclyl, R.sub.3 and R.sub.4 may be the same or different and represent hydrogen, alkyl, alkenyl, aralkyl, aryl or alkoxy, and R.sub.5 is an alkyl radical substituted by one or more chlorine atoms (2,2,2-trichloroethyl, 2-trichloromethylisopropyl).

Abstract: The invention relates to a reagent which is useful for the synthesis of oxysulphide-containing fluorine-containing organic derivatives by reacting with an oxide of sulphur, especially sulphur dioxide, characterized in that it comprises:a) a fluorocarboxylic acid of formula E.sub.w --CF.sub.2 --COOH where E.sub.w is an electron-withdrawing group or atom which is at least partially salified by an organic or inorganic cation, andb) an aprotic polar solvent; andin that the content of releasable protons carried by its various components, including their impurities, is at most equal to half the initial molar concentration of the said fluorocarboxylic acid.This reagent can be used by heating in order to form fluorine-containing sulphinic or sulphonic acids.

Abstract: The invention relates to a process and a nucleophilic reagent which is useful for grafting a substituted difluoromethyl group onto a compound containing at least one electrophilic function, characterized in that it comprises:a) a fluorocarboxylic acid of formula Ew--CF.sub.2 --COOH where Ew represents an electron-withdrawing atom or group, at least partially salified with an organic or inorganic cation, andb) a polar aprotic solvent;and in that the content of releasable protons carried by its various components, including their impurities, is at most equal to half the initial molar concentration of the said fluorocarboxylic acid.

Abstract: The present invention relates to compounds composed essentially of a linear, cyclic or branched polyorganosiloxane having, per molecule, at least 3 siloxy units, including at least one siloxy functional unit of formula: ##STR1## where R.sup.1 represents a C.sub.1 to C.sub.4 alkyl or phenyl radical, X contains an N,N'-di- and/or trisubstituted phenylenediamine functional group, bonded to the silicon via an Si--(hydrocarbon linking unit)--N and/or Si--(hydrocarbon linking unit)--C bond, and a is a number chosen from 0, 1 and 2. The present invention also relates to the use of such compounds as antiozonants for rubbers and in particular for rubber compositions for tires.

Abstract: This invention relates to a method of preparing esters of baccatine III or 10-deacetylbaccatine III of formula (I) by esterification of protected baccatine III or 10-deacetylbaccatine III of formula (II) by means of an activated acid of formula (III). The esters of formula (I) can be used to prepare taxane derivatives having remarkable antileucemia and antitumor properties. In formulae (I), (II) and (III) Ar is an aryl radical, R.sub.1 is a hydrogen atom or an aryl radical or an R.sub.4 --O--CO-- radical (R.sub.4 =alkenyl, alkynyl, optionally substituted alkyl, cycloalkyl, cycloalkynyl, bicycloalkyl, phenyl, heterocyclyle) and R.sub.2 is a hydrogen atom, and R.sub.3 stands for a hydroxy function protection grouping, or R.sub.1 is defined as above and R.sub.2 and R.sub.3 together form a 5 or 6 membered, saturated heterocyclic ring, G.sub.1 is an acetyl radical or a hydroxy function protection grouping, G.sub.2 is a hydroxy function protection grouping, and X is an acyl radical, aryl, radical or halogen atom.

Abstract: Disclosed is a compound of formula VII: ##STR1## where Ar represents an optionally substituted phenyl or .alpha.- or .beta.-naphthyl radical; R.sub.3 represents hydrogen, a C.sub.1-4 alkyl radical, a C.sub.2-4 alkenyl radical, an aralkyl radical, or an aryl radical; and R.sub.4 represents hydrogen, a C.sub.1-4 alkyl radical, a C.sub.2-4 alkenyl radical, an aralkyl radical, or an aryl radical; or alternatively R.sub.3 and R.sub.4, together with the carbon atom to which they are linked, form a 4- to 7-membered ring; and R.sub.5 represents an C.sub.1-4 alkyl radical substituted with at least one chlorine atom. The compound of formula VI may be used to manufacture a compound of formula VIII: ##STR2## where Ar, R.sub.3, R.sub.4 and R.sub.5 are defined above; G.sub.1 represents a group protecting the hydroxyl function; and where appropriate, G.sub.2 represents a group protecting the hydroxyl function.

Abstract: This invention relates to a method of preparing taxane derivatives of general formula (I) by esterification of protected baccatine III or 10-deacetylbaccatine III by means of an acid of general formula (VII), elimination of protection groupings of the ester obtained, and acylation of the amine function of the side chain. In formulae (I) and (VII): Ar stands for aryl, R is hydrogen or acetyl, R.sub.1 is benzoyl or R.sub.2 --CO--O-- in which R.sub.2 is alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, bicycloalkyl, phenyl or heterocyclyl, R.sub.3 and R.sub.4 may be the same or different and represent hydrogen, alkyl, alkenyl, aralkyl, aryl or alkoxy, and R.sub.5 is an alkyl radical substituted by one or more chlorine atoms (2,2,2-trichloroethyl, (2-trichloromethylisopropyl).

Abstract: This invention relates to novel anhydrides of general formula (I), ##STR1## wherein Ar is an aryl radical, and either R.sub.1 is C.sub.6 H.sub.5 --CO or (CH.sub.3).sub.3 C--O--CO, R.sub.2 is a hydrogen atom and R.sub.3 is a hydroxy function protective grouping, or R.sub.1 is (CH.sub.3).sub.3 C--O--CO and R.sub.2 together form a saturated 5 or 6-membered heterocyclic ring; preparation thereof; and uses thereof for preparing taxane derivatives having general formula (III), ##STR2## wherein R=H, acetyl; R.sub.1 is C.sub.6 --H.sub.5 --CO or (CH.sub.3).sub.3 C--O--CO), and having antitumoral properties.

Abstract: A process for the preparation of a brominated compound which comprises the step of reacting at least one compound selected from the group consisting of a chloroformate, a chlorosulfite and a chlorophosphite with a brominating agent for a time sufficient to obtain at least one brominated compound. In particular, an alcohol is converted into a chloroformate, chlorosulfite or a chlorophosphite, which is then brominated to obtain the desired product. In another embodiment, a brominating agent is reacted with a reactant selected from the group consisting of thionyl chloride, phosgene and phosphorous oxychloride, followed by contacting the reaction product obtained with an alcohol to be brominated.