Stabilized N-alkenyllactam

A composition comprising an N—C2 to C6-alkenyl-2-piperidone compound wherein the C2 to C6 alkenyl group is characterized by a double bond in the α-position to the lactam nitrogen and the caprolactam ring optionally may be monosubstituted or polysubstituted by C1 to C4 alkyl groups, stabilized by a phenothiazine compound of the general formula (I)

• wherein the radicals R1 to R8 independently of one another are hydrogen atom, an unsubstituted or substituted aliphatic, aromatic or araliphatic radical having from 1 to 10 carbon atoms, an amino group, a halogen, a nitrogen group or a cyano group, with a total amount of said phenothiazine compound of the general formula (I) of 1 to 1000 ppm by weight, based on the total amount of the N-alkenyllactam.

A process for the stabilization of an N—C2- to C6-alkenylcaprolactam compound wherein the C2 to C6 alkenyl group is characterized by a double bond in the α-position to the lactam nitrogen and the caprolactam ring optionally may be monosubstituted or polysubstituted by C1 to C4 alkyl groups, wherein the N—C2-to C6-alkenylcaprolactam compound is mixed with a phenothiazine compound of the general formula (I)

• wherein the radical R1 to R8 independently of one another are a hydrogen atom, an unsubstituted or substituted aliphatic, aromatic or araliphatic radical having from 1 to 10 carbon atoms, an amino group, a halogen, a nitrogen group or a cyano group, with a total amount of said phenothiazine compound of the general formula (I) of 1 to 1000 ppm by weight, based on the total amount of the N-alkenyllactam.

A process for the stabilization of an N—C2- to C6-alkenyl-2-piperidone compound wherein the C2 to C6 alkenyl group is characterized by a double bond in the α-position to the lactam nitrogen and the caprolactam ring optionally may be monosubstituted or polysubstituted by C1 to C4 alkyl groups, wherein the N—C2- to C6-alkenylcaprolactam compound is mixed with a phenothiazine compound of the general formula (I)

• wherein the radicals R1 to R8 independently of one another are a hydrogen atom, an unsubstituted or substituted aliphatic, aromatic or araliphatic radical having from 1 to 10 carbon atoms, an amino group, a halogen, a nitrogen group or a cyano group, with a total amount of said phenothiazine compound of the general formula (I) of 1 to 1000 ppm by weight, based on the total amount of N-alkenyllactam.