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    Improved process for the preparation of astaxanthine
    41.
    发明专利
    Improved process for the preparation of astaxanthine 未知

    公开(公告)号：DE4430289A1

    公开(公告)日：1995-03-09

    申请号：DE4430289

    申请日：1994-08-26

    Applicant: BASF AG

    Inventor： ERNST HANSGEORG DR ,  PAUST JOACHIM DR ,  DOBLER WALTER DR ,  RHEUDE UDO DR

    IPC: C07C403/16 ,  C07C47/21 ,  C07C69/66 ,  C07C403/00 ,  C07C403/24 ,  C07F9/50 ,  C07F9/54

    Abstract: Process for preparing astaxanthine by reacting A. The tertiary alcohol of the formula II or the diacetate of the formula III with aqueous hydrobromic acid or hydrochloric acid in an inert solvent, B. Reacting the resulting halide of the formula IV with triphenylphosphine in an inert solvent and C. Reacting the resulting triphenylphosphonium salt with 2,7-dimethyl-2,4,6-octatriene-1,8-dial in a Wittig reaction, which is characterised in that, in reaction step B, the halide of the formula IV is reacted with the triphenylphospine in an open-chain lower-dialkyl ether, triphenylphosphonium salt of the formula V being obtained in a form in which it can be readily filtered, and this is reacted in reaction step C in a Wittig reaction with 2,7-dimethyl-2,4,6-octatriene-1,8-dial while simultaneously or subsequently eliminating the acetyl groups, or else in that, in reaction step A, the starting compound of the formula II or III is reacted with aqueous hydrobromic acid or hydrochloric acid in methylene chloride, the resulting solution of the halide of the formula IV is reacted with triphenylphosphine, and the resulting solution of the triphenylphosphonium salt of the formula V is reacted with 2,7-dimethyl-2,4,6-octatriene-1,8-dial in a Wittig reaction in methylene chloride while eliminating the acetyl groups.

    42.
    发明专利
    未知

    公开(公告)号：DE3766536D1

    公开(公告)日：1991-01-17

    申请号：DE3766536

    申请日：1987-05-07

    Applicant: BASF AG

    Inventor： ERNST HANSGEORG DR ,  LEININGER HARTMUT DR ,  PAUST JOACHIM DR

    IPC: C07B61/00 ,  B01J25/00 ,  B01J25/02 ,  C07C67/00 ,  C07C213/00 ,  C07C213/02 ,  C07C215/10 ,  C07C215/16 ,  C07C215/68 ,  C07H5/04

    Abstract: N-(D)-ribitylxylidine (I) is prepared by reacting (D)-ribose (II) with 3,4-dimethylaniline (III) or 3,4-dimethyl-1-nitrobenzene (IV) in aqueous or aqueous/organic solution or in solution in a water-soluble organic solvent under an elevated hydrogen pressure and in the presence of a hydrogenation catalyst and of a boric acid compound, (a) using the boric acid compound in a catalytic amount of from about 6 to 35 mmol, preferably from 6 to 20 mmol, per mol of ribose, (b) carrying out the reaction under a hydrogen pressure of from 1 to 20, preferably from 2 to 9, bar and (c) carrying out the hydrogenation at from 40 DEG to 80 DEG C. over Raney nickel as hydrogenation catalyst.

    OPTICALLY ACTIVE CHROMAN DERIVATIVES, PROCESS FOR THEIR PREPARATION AND INTERMEDIATES
    46.
    发明专利
    OPTICALLY ACTIVE CHROMAN DERIVATIVES, PROCESS FOR THEIR PREPARATION AND INTERMEDIATES 未知

    公开(公告)号：DE3469029D1

    公开(公告)日：1988-03-03

    申请号：DE3469029

    申请日：1984-03-07

    Applicant: BASF AG

    Inventor： GEHRKEN HENNING-PETER DR ,  ERNST HANSGEORG DR ,  PAUST JOACHIM DR

    IPC: C07D311/58 ,  C07D311/72

    Abstract: Novel optically active chroman derivatives of the general formulae Ia and Ib (Ia) (Ib) where R1, R2, R3 and R4 are each hydrogen or alkyl and X is -OH, -O-CO-alkyl, -O-alkyl, -O-tosyl, -O-mesyl, -O-benzenesulfonyl, Cl, Br or I, are prepared by a process in which (a) the racemate of the formula I' (I') is esterified in the side chain with a carboxylic acid and then acylated with an optically active carboxylic acid halide of the general formula III (III) or with the corresponding carboxylic anhydride, to give a chroman derivative IV (IV) or (b) the racemate I' is esterified in the side chain with the carboxylic acid from which III is derived, and, if required, the resulting ester is acylated with a carboxylic acid halide to give IV' (IV') the resulting mixture IV or IV', which consists of two diastereomers, is resolved by fractional crystallization, the diastereomers are hydrolyzed to the alcohols Ia and Ib and, if desired, these are converted to the other compounds Ia and Ib in a conventional manner. Useful optically active chroman derivatives Ia and Ib and diastereomeric chromanyl esters IV and IV' are also claimed.

    Improved process for the preparation of 2-methyl-4-amino-5-aminomethylpyrimidine
    48.
    发明专利
    Improved process for the preparation of 2-methyl-4-amino-5-aminomethylpyrimidine 未知

    公开(公告)号：DE3511273A1

    公开(公告)日：1986-10-09

    申请号：DE3511273

    申请日：1985-03-28

    Applicant: BASF AG

    Inventor： ERNST HANSGEORG DR ,  PAUST JOACHIM DR

    IPC: C07D239/42

    Abstract: Process for the direct preparation of 2-methyl-4-amino-5-aminomethylpyrimidine of the formula I starting from an enolate of alpha -formyl- beta -formylaminopropionitrile of the formula II in which Me represents a metal cation, preferably an alkali metal cation, which is characterised in that the enolate of the formula II is reacted with a salt of the acetamidine in an inert solvent at temperatures from 50 to 150 DEG C and the 2-methyl-4-amino-5-formylaminoemthylpyridine obtained of the formula II is then hydrolysed in a manner known per se. I is an important intermediate for the preparation of vitamin B1.

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