Preparation of trifluoromethyl-substituted phenols and phenates and the preparation, from these phenols and phenates, of nitro- and trifluoromethyl-substituted diphenyl ethers
申请人:ROHM AND HAAS COMPANY
公开号:EP0019388A1
公开(公告)日:1980-11-26
Preparation of trifluoromethyl-substituted phenols and phenates and the preparation, from these phenols and phenates, of nitro- and tri-fluoromethyl-substituted diphenyl ethers.
A novel process is provided for the preparation of a substituted phenate (or the corresponding phenol) of the formula:
wherein X is halo or trifluoromethyl with the proviso that,
when X is halo, X' is trifluoromethyl,
X' is hydrogen, halo, trifluoromethyl or (C1-C4) alkyl, and
M is the cation of an alkali metal or alkaline earth metal,
wherein the process comprises reacting a compound of the formula
(wherein X and X' are as above defined) with an alkali metal or alkaline earth metal hydroxide base in a solvent system which is substantially inertto said base and which comprises a polar, aprotic solvent with a dielectric constant in the range of from about 30 to about 70 and a non-nucleophilic hydroxy-containing solvent which increases the solubility of said base in the solvent system whereby a phenate is obtained and, if a phenol is the desired product, reacting the phenate with an acid to form the phenol.
The phenates or phenols obtainable by the novel process may be used as intermediates in the preparation of trifluoromethylphenyl nitrophenylether herbicides optionally containing one or two additional ring substituents
制备三氟甲基取代的苯酚和苯甲酸酯以及用这些苯酚和苯甲酸酯制备硝基和三氟甲基取代的二苯醚。
本发明提供了一种新工艺,用于制备式中的取代苯甲酸酯(或相应的苯酚):
其中 X 为卤代或三氟甲基,但有以下条件
当 X 为卤素时,X'为三氟甲基、
X'是氢、卤素、三氟甲基或(C1-C4)烷基,以及
M 是碱金属或碱土金属的阳离子、
其中,该工艺包括使以下式子的化合物发生反应
(其中 X 和 X'如上定义)与碱金属或碱土金属氢氧化物碱在溶剂体系中反应,该溶剂体系对所述碱基本上是惰性的,它包括介电常数在约 30 至约 70 范围内的极性烷基溶剂和可增加所述碱在溶剂体系中溶解度的非亲核含羟基溶剂,从而得到苯酸盐,如果苯酚是所需产物,则使苯酸盐与酸反应生成苯酚。
通过新工艺得到的苯酸盐或苯酚可用作中间体,用于制备三氟甲基苯基硝基苯基醚除草剂,该除草剂可选择含有一个或两个额外的环取代基。