Process for the preparation of hydroxyphenylpropionic acid esters

An improved process for the preparation of a compound of the general formula V ##STR103## in which R.sub.o is hydrogen or C.sub.1 -C.sub.4 alkyl, and

• R is C.sub.1 -C.sub.4 alkyl,
• reacting 2,6-di-tert-butylphenol with an acrylate of the formula VI ##STR104## in which R.sub.0 and R are as defined above, which improvement comprises carrying out the reaction in the presence of a catalyst which contains, as active material, a component of the formula IV
• M.sub.m An (IV)
• in which
• M is Na, K, Rb or Cs,
• m is the valency of An and
• An is a fluoride, hydroxide or --OR.sub.5 radical, and R.sub.5 is C.sub.1 -C.sub.4 alkyl or phenyl,
• and, as support, an alkaline material which, measured in 10% strength by weight aqueous suspension, has a pH >10, selected from one or more groups of substances from the series consisting of the hydrated alkaline earth metal oxides, aluminates and silicates.

An improved process for the preparation of a compound of the general formula VII ##STR105## in which R.sub.0 is hydrogen or C.sub.1 -C.sub.4 alkyl, and

• n is 1, 2, 3, 4 or 6, and
• if n=1,
• A is --OR.sub.4 in which
• R.sub.4 is C.sub.2 -C.sub.45 alkyl, C.sub.5 -C.sub.12 cycloalkyl, C.sub.2 -C.sub.18 alkenyl, ##STR106## or --CH.sub.2 CH.sub.2 --XR.sub.5a, in which R.sub.9 is hydrogen, C.sub.1 -C.sub.8 alkyl, ##STR107## --O. or --OR.sub.9', in which, R.sub.9' is hydrogen or C.sub.1 -C.sub.25 alkyl or ##STR108## R.sub.10 is hydrogen or alkyl having 1 to 20 carbon atoms, X is --O--, --S-- or ##STR109## R.sub.5a is ##STR110## hydrogen, C.sub.1-C.sub.24 alkyl, phenyl, C.sub.5 -C.sub.12 cycloalkyl or ##STR111## in which R.sub.a is hydrogen or methyl,
• R.sub.b is hydrogen or C.sub.1 -C.sub.24 alkyl and
• R.sub.c is hydrogen or methyl, with the proviso that R.sub.a and R.sub.c are not simultaneously methyl, and
• R.sub.6a is C.sub.1 -C.sub.18 alkyl, phenyl, phenyl which is substituted by one or more alkyl groups having a total of 1 to 24 carbon atoms, or is C.sub.5 -C.sub.8 cycloalkyl, or,
• if n=2,
• A is --O--C.sub.x H.sub.2x --O--, --O--(CH.sub.2 CH.sub.2 O).sub.a CH.sub.2 CH.sub.2 O--, --O--CH.sub.2 --CH.sub.2 --B--CH.sub.2 CH.sub.2 O--, ##STR112## --O--CH.sub.2 CH.dbd.CHCH.sub.2 --O--, --O--CH.sub.2 C.tbd.CCH.sub.2 --O--, ##STR113## in which a is a number from 1 to 30
• x is a number from 2 to 20,
• B is --S--, ##STR114## in which R.sub.A is C.sub.1 -C.sub.20 alkyl having 1 to 20 carbon atoms, phenyl, phenyl which is substituted by one or more alkyl groups having a total of 1 to 20 carbon atoms, or is cyclohexyl or ##STR115## where R.sub.9 is as defined above, and R.sub.12 and R.sub.13, independently of one another, are hydrogen, C.sub.1 -C.sub.12 alkyl or phenyl, or
• R.sub.12 and R.sub.13, together with the carbon atom to which they are bonded, form a cycloalkyl ring having 5 to 12 carbon atoms, and
• b.sub.1 is a number from 2 to 10, or
• if n=3,
• A is ##STR116## in which R.sub.f is C.sub.1 -C.sub.24 alkyl or phenyl, or,
• if n=4,
• A is ##STR117## if n=6, A is ##STR118## which improvement comprises reacting a compound of the formula VI ##STR119## in which R.sub.0 is hydrogen or C.sub.1 -C.sub.4 alkyl and R is C.sub.1 -C.sub.4 alkyl, with 2,6-di-tert-butylphenol in a first step to give a compound of the formula V, and reacting the latter, without isolation from the reaction mixture, in a second step with a compound of the formula III ##STR120## where A and n are as defined above, both steps being carried out in the presence of a catalyst which contains, as active material, a component of the formula IV
• M.sub.m An (IV)
• in which
• M is Na, K, Rb or Cs,
• m is the valency of An and
• An is a fluoride, hydroxide or --OR.sub.5 radical, and R.sub.5 is C.sub.1 -C.sub.4 alkyl or phenyl,
• and, as support, an alkaline material which, measured in 10% strength by weight suspension, has a pH>10, selected from one or more groups of substances from the series consisting of the hydrated alkaline earth metal oxides, aluminates and silicates.