31.
    发明专利
    未知

    公开(公告)号:FR2735468A1

    公开(公告)日:1996-12-20

    申请号:FR9506449

    申请日:1995-05-31

    Abstract: A method for preparing a meta-dihydroxylated aromatic compound, and more particularly for preparing resorcin or 1,3-diphenol is described. The preparation of a meta-dihydroxylated aromatic acid as an intermediate is also described. The method for preparing a meta-dihydroxylated aromatic compound includes the steps of successively or simultaneously hydroxylating and decarboxylating an aromatic compound bearing one or more carboxylic and/or carboxylate groups and, on either side, in the ortho position, a hydroxyl group and a hydrogen atom.

    33.
    发明专利
    未知

    公开(公告)号:NO964463D0

    公开(公告)日:1996-10-21

    申请号:NO964463

    申请日:1996-10-21

    Abstract: PCT No. PCT/FR96/00241 Sec. 371 Date Oct. 16, 1996 Sec. 102(e) Date Oct. 16, 1996 PCT Filed Feb. 14, 1996 PCT Pub. No. WO96/26175 PCT Pub. Date Aug. 29, 1996The subject of the present invention is a process for the preparation of a 4-hydroxybenzaldehyde carrying at least one substituent in the position ortho to the OH group. It more particularly relates to the preparation of 3-methoxy-4-hydroxybenzaldehyde and of 3-ethoxy-4-hydroxybenzaldehyde. The process for the preparation of a substituted 4-hydroxybenzaldlehyde, substituted at least in the 3 position by an alkoxy group, is characterized in that it comprises subjecting a substituted phenol compound, substituted at least in the 2 position by an alkoxy group and in which the 4 and 6 positions are free, to a first stage of carboxylation in the 6 position, then to a stage of hydroxymethylation in the 4 position, followed by a stage of oxidation of the hydroxymethyl group to a formyl group, and finally to a last decarboxylation stage.\!

    34.
    发明专利
    未知

    公开(公告)号:FI964190A0

    公开(公告)日:1996-10-18

    申请号:FI964190

    申请日:1996-10-18

    Abstract: PCT No. PCT/FR96/00241 Sec. 371 Date Oct. 16, 1996 Sec. 102(e) Date Oct. 16, 1996 PCT Filed Feb. 14, 1996 PCT Pub. No. WO96/26175 PCT Pub. Date Aug. 29, 1996The subject of the present invention is a process for the preparation of a 4-hydroxybenzaldehyde carrying at least one substituent in the position ortho to the OH group. It more particularly relates to the preparation of 3-methoxy-4-hydroxybenzaldehyde and of 3-ethoxy-4-hydroxybenzaldehyde. The process for the preparation of a substituted 4-hydroxybenzaldlehyde, substituted at least in the 3 position by an alkoxy group, is characterized in that it comprises subjecting a substituted phenol compound, substituted at least in the 2 position by an alkoxy group and in which the 4 and 6 positions are free, to a first stage of carboxylation in the 6 position, then to a stage of hydroxymethylation in the 4 position, followed by a stage of oxidation of the hydroxymethyl group to a formyl group, and finally to a last decarboxylation stage.\!

    Method for preparing a substituted 4-hydroxybenzaldehyde

    公开(公告)号:AU4870096A

    公开(公告)日:1996-09-11

    申请号:AU4870096

    申请日:1996-02-14

    Abstract: PCT No. PCT/FR96/00241 Sec. 371 Date Oct. 16, 1996 Sec. 102(e) Date Oct. 16, 1996 PCT Filed Feb. 14, 1996 PCT Pub. No. WO96/26175 PCT Pub. Date Aug. 29, 1996The subject of the present invention is a process for the preparation of a 4-hydroxybenzaldehyde carrying at least one substituent in the position ortho to the OH group. It more particularly relates to the preparation of 3-methoxy-4-hydroxybenzaldehyde and of 3-ethoxy-4-hydroxybenzaldehyde. The process for the preparation of a substituted 4-hydroxybenzaldlehyde, substituted at least in the 3 position by an alkoxy group, is characterized in that it comprises subjecting a substituted phenol compound, substituted at least in the 2 position by an alkoxy group and in which the 4 and 6 positions are free, to a first stage of carboxylation in the 6 position, then to a stage of hydroxymethylation in the 4 position, followed by a stage of oxidation of the hydroxymethyl group to a formyl group, and finally to a last decarboxylation stage.\!

    PROCESS FOR THE PREPARATION OF PICRIC ACID

    公开(公告)号:HUT73556A

    公开(公告)日:1996-08-28

    申请号:HU9502635

    申请日:1995-09-08

    Abstract: Prepn. of picric acid comprises nitrating o-nitrophenol and/or p-nitrophenol to dinitrophenols such that the intermediate(s) formed remain soluble in the reaction medium. Nitration is then continued to obtain picric acid which pptes. Either nitric acid or the nitrating mixt. is introduced into the nitrophenol; or the nitrophenol is progressively introduced to the reaction medium comprising nitric acid or the nitrating mixt.; or the nitrophenol and the nitric acid or nitrating mixt. are simultaneously introduced on a first bottoms mixt. comprising water or co-acid. The nitrating mixt. is nitric acid associated with a strong co-acid.

    38.
    发明专利
    未知

    公开(公告)号:FR2724651A1

    公开(公告)日:1996-03-22

    申请号:FR9411050

    申请日:1994-09-16

    Abstract: Prepn. of mono- and di-carboxylic acids from unsatd. fatty acids and/or derivs., comprises: (i) oxidising an unsatd. fatty acid, in the form of an acid and/or ester, with hydrogen peroxide in presence of a metal oxide or a carboxylic acid, opt. with a ruthenium catalyst; (ii) reacting the mixt. with nitric acid in presence of a vanadium catalyst, opt. with a co-catalyst; and (iii) recovering the mono- and di-carboxylic acids. The starting material is pref. a fatty acid with at least one double bond, an animal fat or oil, a vegetable oil, an ester of a pptd. fatty acid and is pref. oleic, colza, sunflower and soya oil. The ruthenium catalyst is pref. present in amt. of 1-35 % w.r.t. H2O2. H2O2 may be used with a gp. VIa metal catalyst, esp. a W and/or Mo catalyst in amt. of 1-35 (pref. 3-10) %, w.r.t. H2O2. The vanadium catalyst may be a V halide, a V oxide, a V oxyhalide, a V or vanadyl sulphate, an alkali metal or ammonium vanadate, or V acetylacetonate. The optional V co-catalyst may be based on a Gp. VIIa or VIII metal. A stoichiometric amt. of H2O2 or a 0-50 % excess is used with a carboxylic acid in a hydrogen peroxide : carboxylic acid molar ratio of 10-500 (pref. 10-40) %.

    40.
    发明专利
    未知

    公开(公告)号:DE69007814D1

    公开(公告)日:1994-05-11

    申请号:DE69007814

    申请日:1990-01-22

    Abstract: Process for the preparation of an optically active 2-chloropropionate ester of formula: R being an optionally substituted hydrocarbyl residue, from an optically active lactate of formula the said process being characterised in that the said lactate (I) is brought into contact with phosgene and a compound chosen from aliphatic amides, aliphatic lactams and aliphatic ureas. Use of the process for the manufacture of intermediates which are useful in the agrochemical industry.

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