Patent ID: 6117995
Filing Date: 2000-09-12
Classification: C07D,C08K,C09K

Abstract:
A process for the preparation of a compound of the formula (I) ##STR79## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4, independently of each other, are C.sub.1 -C.sub.8 alkyl or C.sub.1 -C.sub.5 hydroxyalkyl, or R.sub.1 and R.sub.2 together with the carbon atom they are attached to are C.sub.5 -C.sub.12 cycloalkyl, or R.sub.3 and R.sub.4 together with the carbon atom they are attached to are C.sub.5 -C.sub.12 cycloalkyl;R.sub.5, R.sub.6, R.sub.7, R.sub.8 and R.sub.9, independently of each other, are H; C.sub.1 -C.sub.8 alkyl; C.sub.2 -C.sub.8 alkenyl; C.sub.5 -C.sub.12 aryl; C.sub.1 -C.sub.4 haloalkyl; an electron withdrawing group selected from the group consisting of CN, nitro, halogen and --COOR.sub.10, where R.sub.10 is C.sub.1 -C.sub.12 alkyl or C.sub.5 -C.sub.12 cycloalkyl or C.sub.7 -C.sub.9 phenylalkyl or phenyl; or R.sub.5, R.sub.4. R.sub.7, R.sub.8 and R.sub.9, independently of each other, are C.sub.6 -C.sub.12 aryl which is substituted by a residue selected from C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, halogen; and R.sub.7 and R.sub.8 together may also form a chemical bond; andthe linking group R forms, together with the carbon atoms it is directly connected to and the nitrogen atom, a substituted, 5-, 6 or 7-membered cyclic ring structure;wherein a compound of the formula (II) ##STR80## wherein all residues R and R.sub.1 -R.sub.9 are as defined for formula (I), is oxidized.