发明名称 |
High caustic coupling process for preparing substituted 2-nitro-2'-hydroxyazobenzenes |
摘要 |
Substituted 2-nitro-2'hydroxyazobenzenes are prepared by adding an aqueous mineral acid solution of a diazotized o-nitroaniline to a strongly alkaline lower alkanol or aqueous lower alkanol solution of a substituted phenol, containing sufficient alkali metal hydroxide to assure a pH value substantially over 11 and an excess of hydroxyl ion in the reaction mixture even after all the acidic diazonium salt solution is added, wherein the reaction solvent mixture is at least 50% by weight of lower alkanol, at a reaction temperature between -15 DEG C. and +30 DEG C. The o-nitroazobenzenes obtained are intermediate products useful in the manufacture of benzotriazole UV absorbers.
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申请公布号 |
US4275004(A) |
申请公布日期 |
1981.06.23 |
申请号 |
US19790038768 |
申请日期 |
1979.05.16 |
申请人 |
CIBA-GEIGY CORPORATION |
发明人 |
WINTER, ROLAND A. E.;DEXTER, MARTIN |
分类号 |
C07C37/14;C07D249/20;C08K5/3475;C09B29/15;C09D7/12;(IPC1-7):C07C107/06;C09B29/12 |
主分类号 |
C07C37/14 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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