申请人:Junsei Chemical Co., Ltd.
公开号:US05847231A1
公开(公告)日:1998-12-08
Process for preparing 4-nitrophenol derivatives of formula (IV) with high selectivity, which comprises converting phenols to diphenyl oxalate derivatives of formula (III) and conducting nitration reaction and hydrolysis to give said 4-nitrophenol derivatives. ##STR1## In the above formulae, R is, the same or different from each other, an alkyl group having 1 to 4 carbon atoms; a halogen atom; an alkoxy group having 1 to 4 carbon atoms; a formyl group; a nitrile group; --COOR.sup.1 (R.sup.1 is an alkyl group having 1 to 4 carbon atoms); --CONR.sup.2 R.sup.3 (R.sup.2 and R.sup.3 are, the same or different from each other, hydrogen atom(s) or alkyl group(s) having 1 to 4 carbon atoms); or --COR.sup.4 (R.sup.4 is an alkyl group having 1 to 4 carbon atoms), and R is not substituted at the 4-position of the phenyl ring and not substituted at the 2- and 6-positions of the phenyl ring at the same time, and, n is 1, 2 or 3.
制备具有高选择性的4-硝基苯酚衍生物(IV)的过程,包括将苯酚转化为配方(III)的二苯基草酸酯衍生物,然后进行硝化反应和水解以得到所述的4-硝基苯酚衍生物。在上述公式中,R是1至4个碳原子的同一或不同的烷基基团;卤素原子;1至4个碳原子的同一或不同的烷氧基团;甲酰基团;腈基团;-COOR^1(R^1是1至4个碳原子的烷基基团);-CONR^2R^3(R^2和R^3是同一或不同的氢原子或1至4个碳原子的烷基基团);或-COR^4(R^4是1至4个碳原子的烷基基团),且R在苯环的4位不被取代,在2位和6位同时不被取代,n为1、2或3。