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351 条记录 (耗时 0.013 秒)

    PRODUCTION OF GLYCOLLIC ACIDS
    26.
    发明专利
    PRODUCTION OF GLYCOLLIC ACIDS 失效

    公开(公告)号：JPH05320096A

    公开(公告)日：1993-12-03

    申请号：JP30406491

    申请日：1991-10-22

    申请人： NIPPON SYNTHETIC CHEM IND

    发明人： YAMAMOTO TOSHIO

    IPC分类号： C07C67/31 ,  C07C69/675 ,  C07C233/04 ,  C07C233/13 ,  C07C233/16

    摘要： PURPOSE:To industrially and advantageously obtain a glycollic acid useful as an intermediate for agricultural chemicals, especially herbicides by reacting specific alpha-halogenoacetic acids with a specific carboxylic acid salt using a mixed solvent of methanol and water as a solvent. CONSTITUTION:An alpha-halogenoacetic acid expressed by formula I [X is chlorine or bromine; R1 and R2 are H or alkyl; R3 is the formula OR' (R' is alkyl) or the formula NR'' R''' (R'' and R''' are H, alkyl or aryl)] (e.g. N,N- methylphenyl-alpha-chloroacetic acid amide) is made to react with a carboxylic acid salt expressed by formula II (R is H or alkyl; M is alkali metal or alkaline earth metal) (e.g. sodium acetate) using a mixed solvent of methanol and water as a solvent at 67 deg.C for 22hr and then methanol is distilled off under reduced pressure and ethyl acetate and water are added to the residue and hydrochloric acid is dropped thereto to control pH to 4 and an organic layer is separated and the solvent is distilled off under reduced pressure to provide the objective glycollic acid expressed by formula III in ordinary reaction without using the catalyst.

    NEW BISMALEIMIDE AND ITS PRODUCTION
    27.
    发明专利
    NEW BISMALEIMIDE AND ITS PRODUCTION 失效

    公开(公告)号：JPH05230018A

    公开(公告)日：1993-09-07

    申请号：JP3171492

    申请日：1992-02-19

    申请人： MITSUI TOATSU CHEMICALS

    发明人： TAKAGI MASATOSHI ,  KAMEOKA TAIJI ,  KATO TOSHIO ,  HASEYAMA RYUJI

    IPC分类号： C07D207/452 ,  C07C233/09 ,  C07C233/13 ,  C07D207/456 ,  C08F22/36 ,  C08F222/40

    摘要： PURPOSE:To provide a new bismaleimide capable of giving transparent, flexible polyimide resins without impairing high heat resistance inherent in them. CONSTITUTION:The objective bismaleimide of formula I (R is H, halogen or methyl; X and Y are each H, halogen or 1-10C alkyl), e.g. norbornane- bismethylmaleimide. The maleimide of the formula I can be obtained by cyclodehydration of a bismaleamic acid of formula II. This bismaleamic acid can be prepared by addition reaction between an alicyclic diamine compound of formula III and maleic acid anhydride or its derivative of formula IV.