abstract |
Compounds of the formula I <IMAGE> (I) wherein R, R1, R2, R3, R4 and R5 have the meaning given in claim 1 are formed by thermal rearrangement of the isomers of formula V <IMAGE> (V) especially in the presence of basic catalysts. The compounds are corrosion inhibitors for organic materials, in particular coating materials and lubricants. In these substrates they also act as antioxidants and light-stabilizers and are very stable to heat. |