Substituted malonic acid derivatives and their use as stabilizers

A member of the group consisting of a compound of the formula Ia ##STR66## and an acid addition salt thereof, wherein n is 1 or 2,

• R.sub.a represents alkyl having 1-6 carbon atoms,
• R.sub.b represents alkyl having 1-6 carbon atoms,
• R.sub.c represents alkyl having 1-9 carbon atoms, phenyl benzyl or phenylethyl,
• R.sub.d represents alkyl having 1-6 carbon atoms, or
• R.sub.c and R.sub.d together represent tetra- or pentamethylene,
• R.sub.e represents hydrogen, alkyl having 1-5 carbon atoms, alkenyl or alkynyl having 3-4 carbon atoms or aralkyl having 7-8 carbon atoms,
• R.sub.f represents hydrogen, alkyl having 1-5 carbon atoms, alkenyl or alkynyl having 3-4 carbon atoms, or aralkyl having 7-8 carbon atoms, with R.sub.e and R.sub.f being mutually exchangeable, and
• R.sup.1 represents hydrogen, --O.sup.., --OH, alkyl having 1-12 carbon atoms, alkenyl having 3 or 4 carbon atoms, propargyl, benzyl or a group of the formula --CH.sub.2 --CH(OR.sup.5)--R.sup.4 wherein R.sup.4 represents hydrogen, methyl or phenyl, and R.sup.5 represents hydrogen or a group A--CO--, or R.sup.1 represents a group A--CO--, and in both cases A represents alkyl having 1-12 carbon atoms, alkenyl having 2 or 3 carbon atoms, cyclohexyl, phenyl, benzyl, a phenyl or phenylethyl group substituted by 2 alkyl groups each having 1-4 carbon atoms and a hydroxyl group, alkylamino having 1-12 carbon atoms, dialkylamino having 2-16 carbon atoms, anilino, alkoxy having 1-12 carbon atoms, benzyloxy or phenoxy,
• R.sup.2 represents a hydroxybenzyl group of the formula II ##STR67## wherein R.sup.6 and R.sup.7 each independently represent an alkyl group having 1-9 carbon atoms, aralkyl having 7-9 carbon atoms or cycloalkyl having 5-8 carbon atoms, and R.sup.8 represents hydrogen or methyl, and
• R.sup.3 represents, in the case where n is 1, alkyl having 1-20 carbon atoms, or alkyl having 1-10 carbon atoms, which is substituted by one of the groups --OR.sup.9, --SR.sup.10, --CO--R.sup.11, --CN, --CO--OR.sup.12, --O--C(O)R.sup.13 or --P(O)(OR.sup.14).sub.2, wherein
• R.sup.9 denotes phenyl or alkylphenyl having 7-10 carbon atoms, benzyl or cyclohexyl,
• R.sup.10 represents phenyl or alkylphenyl having 7-10 carbon atoms,
• R.sup.11 denotes alkyl having 1-12 carbon atoms,
• R.sup.12 denotes having 1-18 carbon atoms, cycloalkyl having 5-12 carbon atoms, or a group of the formula IIIb ##STR68## R.sup.13 denotes alkyl having 1-17 carbon atoms, cycloalkyl having 5-12 carbon atoms, or phenyl or phenylalkyl having 7-9 carbon atoms, wherein the phenyl radical is unsubstituted or substituted by at least one of the groups alkyl having 1-4 carbon atoms and hydroxyl, and
• R.sup.14 denotes alkyl having 1-8 carbon atoms, allyl or phenyl, and
• R.sup.3 further represents an alkyl group having 2-22 carbon atoms, which is interrupted by --O--, --S--, --SO-- or --SO.sub.2 --, alkenyl having 3-18 carbon atoms, alkynyl having 3-8 carbon atoms, cycloalkyl having 5-12 carbon atoms, alkyl-cycloalkyl having 6-18 carbon atoms, cycloalkyl-alkyl having 6-14 carbon atoms, aralkyl or alkyl-aralkyl having 7-19 carbon atoms, or phenyl, and, in addition
• R.sup.3 represents, in the case where n is 2, a direct bond, alkylene having 1-20 carbon atoms, alkylene having 2-20 carbon atoms, which is interrupted by one or two of the members --O--, --S--, --SO--, --SO.sub.2 -- or --CO--O--, arylene-bis-alkylene having 8-14 carbon atoms, alkenylene having 4-8 carbon atoms, or alkynylene having 4-8 carbon atoms.

A member selected from the group consisting of a compound of the formula VIII ##STR69## and an acid addition salt thereof, wherein n is 1 or 2,

• R.sub.a represents alkyl having 1-6 carbon atoms,
• R.sub.b represents alkyl having 1-6 carbon atoms,
• R.sub.c represents alkyl having 1-9 carbon atoms, phenyl, benzyl or phenylethyl,
• R.sub.d represents alkyl having 1-6 carbon atoms, or
• R.sub.c and R.sub.d together represent tetra- or pentamethylene,
• R.sub.e represents hydrogen, alkyl having 1-5 carbon atoms, alkenyl having 3-4 carbon atoms, alkynyl having 3-4 carbon atoms or aralkyl having 7-8 carbon atoms,
• R.sub.f represents hydrogen, alkyl having 1-5 carbon atoms, alkenyl having 3-4 carbon atoms or aralkyl having 7-8 carbon atoms, with R.sub.e and R.sub.f being mutually exchangeable, and
• X represents oxygen or --NR--,
• R represents hydrogen, alkyl having 1-18 carbon atoms, alkenyl having 3-4 carbon atoms, alkynyl having 3-4 carbon atoms, cycloalkyl having 5-12 carbon atoms, aryl having 6-10 carbon atoms, or aralkyl having 7-9 carbon atoms,
• R.sup.1 represents hydrogen, --O;
• --OH, alkyl having 1-12 carbon atoms, alkenyl having 3 or 4 carbon atoms, propargyl, benzyl or a group of the formula --CH.sub.2 --CH(OR.sup.5)--R.sup.4 wherein R.sup.4 represents hydrogen, methyl or phenyl, and R.sup.5 represents hydrogen or a group A--CO--, or R.sup.1 represents a group A--CO--, and in both cases A represents alkyl having 1-12 carbon atoms, alkenyl having 2 or 3 carbon atoms, cyclohexyl, phenyl, benzyl, a phenyl or phenylethyl group substituted by 2 alkyl groups each having 1-4 carbon atoms and a hydroxyl group, alkylamino having 1-12 carbon atoms, dialkylamino having 2-16 carbon atoms, anilino, alkoxy having 1-12 carbon atoms, benzyloxy or phenoxy,
• R.sup.3 represents, in the case where n is 1, alkyl having 1-20 carbon atoms, or alkyl having 1-10 carbon atoms, which is substituted by one or more of the groups --OR.sup.9, --SR.sup.10, --CO--R.sup.11, --CN, --C(O)--YR.sup.12, --O--C(O)R.sup.13 or --P(O)(OR.sup.14).sub.2, wherein
• R.sup.9 denotes phenyl or alkylphenyl having 6-10 carbon atoms, benzyl or cyclohexyl,
• R.sup.10 represents phenyl or alkylphenyl having 6-10 carbon atoms,
• R.sup.11 denotes alkyl having 1-12 carbon atoms, Y represents --O-- or --NR-- wherein R is as previously defined,
• R.sup.12 denotes alkyl having 1-18 carbon atoms, cycloalkyl having 5-12 carbon atoms, or a group of the formula IIIb ##STR70## wherein R.sup.17 represents a group as defined for R', R13 denotes alkyl having 1-17 carbon atoms, cycloalkyl having 5-12 carbon atoms, or phenyl or phenylalkyl having 7-9 carbon atoms, wherein the phenyl radical is unsubstituted or is substituted by at least one of the groups alkyl having 1-4 carbon atoms and hydroxyl, and
• R.sup.14 denotes alkyl having 1-8 carbon atoms, allyl or phenyl, and X has the above-defined meaning, and
• R.sup.3 further represents an alkyl group having 2-22 carbon atoms, which is interrupted by --O--, --S--, --SO-- or --SO.sub.2 --, alkenyl having 3-18 carbon atoms, alkynyl having 3-8 carbon atoms, cycloalkyl having 5-12 carbon atoms, alkyl-cycloalkyl having 6-18 carbon atoms, cycloalkyl-alkyl having 6-14 carbon atoms, aralkyl or alkyl-aralkyl having 7-19 carbon atoms, phenyl, or a group --OR.sup.15, wherein R.sup.15 is alkyl having 1-18 carbon atoms, alkenyl having 3-4 carbon atoms, alkynyl having 3-4 carbon atoms, cycloalkyl having 5-12 carbon atoms or aralkyl having 7-9 carbon atoms, or R.sup.3 represents a group --O--C(O)R.sup.16 or --NH--C(O)R.sup.16, wherein R.sup.16 is alkyl having 1-12 carbon atoms, alkenyl having 2 or 3 carbon atoms, cyclohexyl, phenyl, benzyl, a phenyl or phenylethyl group substituted by 2 alkyl groups each having 1- 4 carbon atoms and a hydroxyl group, or R.sup.3 is a group of the formula III or of the formula IV ##STR71## wherein R.sup.18 represents alkyl having 1-20 carbon atoms, allyl, benzyl, phenyl, cyclohexyl, alkoxyalkyl having 3-8 carbon atoms, or a group --O--C(O)R.sup.16 or --NH--C(O)R.sup.16 as defined above, or has one of the meanings given for R.sup.2, and R.sup.19 and R.sup.20 each independently represent alkyl having 1-6 carbon atoms, or a radical of the formula III, and, in addition,
• R.sup.3 represents, in the case where n is 2, a direct bond, alkylene having 1-20 carbon atoms, alkylene having 2-20 carbon atoms, which is interrupted by one or two of the members --O--, --S--, --SO--, --SO.sub.2 -- or --CO--O--, arylene-bis-alkylene having 8-14 carbon atoms, alkenylene having 4-8 carbon atoms, or alkynylene having 4-8 carbon atoms.