US 5,847,231 A · Selective nitration of phenol derivatives

Abstract

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.

Claims14

Dependent claims

A process for preparing a 4-nitrophenol derivative represented by the following formula (IV):

##STR9## wherein 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,
by selective nitration procedure which comprises:
(A) reacting a phenol derivative of the following formula (I):
##STR10## wherein R and n have the same meanings as above, with an oxalyl halide to give a diphenyl oxalate derivative of the following formula (II):
##STR11## wherein R and n have the same meanings as above, (B) nitrating the derivative of formula (II) with a mixture of concentrated sulfuric acid and nitric acid to give a bis(4-nitrophenyl) oxalate derivative of the following formula (III):
##STR12## wherein R and n have the same meanings as above, and (C) hydrolyzing the derivative of formula (III) to give said 4-nitrophenol derivative of formula (IV).

12 more elements

A process for preparing a 4-nitrophenol derivative represented by the following formula (IV):

##STR17## wherein 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,
by selective nitration procedure which comprises:
(A) reacting a phenol derivative of the following formula (I):
##STR18## wherein R and n have the same meanings as above, with oxalic acid or a reactive derivative thereof, to give a diphenyl oxalate derivative of the following formula (II):
##STR19## wherein R and n have the same meanings as above;
(B) nitrating the derivative of formula (II) with a reagent selected from the group consisting of a mixture of concentrated sulfuric acid and nitric acid, nitric acid, an alkali metal salt of nitric acid in concentrated sulfuric acid, nitrous acetyl, a nitronium salt, and nitric oxide to give a bis(4-nitrophenyl) oxalate derivative of the following formula (III):
##STR20## wherein R and n have the same meanings as above;
and (C) hydrolyzing the derivative of formula (III) to give said 4-nitrophenol derivative of formula (IV).

14 more elements

A process for preparing a 4-nitrophenol derivative represented by the following formula (IV):

##STR21## wherein 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,
by selective nitration procedure which comprises:
(A) reacting a phenol derivative of the following formula (1):
##STR22## wherein R and n have the same meanings as above, with oxalic acid or a reactive derivative thereof, to give a diphenyl oxalate derivative of the following formula (II):
##STR23## wherein R and n have the same meanings as above;
(B) nitrating the derivative of formula (II) to give a bis(4-nitrophenyl) oxalate derivative of the following formula (III):
##STR24## wherein R and n have the same meanings as above;
and (C) hydrolyzing the derivative of formula (III) with an alcohol to give said 4-nitrophenol derivative of formula (IV).

14 more elements

Dependencies are inferred from the claim text.

Selective nitration of phenol derivatives

Life of this patent

Selective nitration of phenol derivatives

Life of this patent

Abstract

Claims14