Abstract: Bis-(2,2,6,6-tetramethyl-piperidyl)diimides are provided, having the formula: ##STR1## in which R is selected from the group consisting of hydrogen; oxyl; alkyl and alkenyl having from one to about eighteen carbon atoms; epoxy and hydroxyalkyl having from two to about eight carbon atoms; acyl having from two to about eight carbon atoms; and phenalkyl having from seven to about twelve carbon atoms; and Z is a tetravalent aliphatic or cycloaliphatic hydrocarbon group having from two to about eighteen carbon atoms; and stabilizer and synthetic polymer compositions containing such diimides having improved resistance to deterioration when exposed to light.

Abstract: Vinyl benzyl 2,2,6,6-tetramethyl piperidines are provided, having the formula: ##STR1## wherein: R is selected from the group consisting of hydrogen; oxyl; acyl and alkyl having from one to about eighteen carbon atoms; ##STR2## in which Y is --O-- or --N(R.sub.2)--, R.sub.1 is alkyl having from one to about eighteen carbon atoms and R.sub.2 is hydrogen or alkyl having from one to about eighteen carbon atoms.

Abstract: Vinyl benzyl 2,2,6,6-tetramethyl piperidines are provided, having the formula: ##STR1## wherein: R is selected from the group consisting of hydrogen; oxyl; acyl and alkyl having from one to about eighteen carbon atoms;X is ##STR2## in which Y is --O-- or--N(R.sub.2)--, R.sub.1 is alkyl having from one to about eighteen carbon atoms and R.sub.2 is hydrogen or alkyl having from one to about eighteen carbon atoms.

Abstract: A process is provided for preparing triacetone amine (2,2,6,6-tetramethyl-4-oxo piperidine) by reacting acetone and/or an acid condensate of acetone with ammonia in the presence of at least one catalyst selected from the group consisting of organotin halides, 1,3,5,2,4,6-triazatriphosphorin hexahalides and cyanuric halides.

Abstract: N-2-Hydroxypropyl piperidines are provided, as well as a process for preparing these compounds, having the formula: ##STR1## wherein X is selected from the group consisting of , ##STR2## wherein R.sub.1 is selected from the group consisting of hydrogen; alkyl; alkenyl; cycloalkyl; alkaryl; hydroxyalkyl; oxyalkyl; acyl and aroyl having from one to about eighteen carbon atoms;R.sub.2 and R.sub.3 are each selected from the group consisting of alkyl, alkenyl, cycloalkyl, alkaryl, hydroxyalkyl, oxyalkyl and haloalkyl having from one to about eighteen carbon atoms;R.sub.4, R.sub.5 and R.sub.6 each are selected from the group consisting of hydrogen, alkyl, alkenyl, cycloalkyl, alkaryl, hydroxyalkyl, oxyalkyl and haloalkyl having from one to about eighteen carbon atoms; and --CH.sub.2 --O--R.sub.1 ;n is 1 or 2; andY, when n is 1, is hydroxy or ##STR3## and when n is 2, is oxyoxygen.

Abstract: There is disclosed a process for preparing 2,2,6,6-Tetramethyl-4-oxopiperidine (triacetoneamine), in which a hydrazine hydrohalide salt catalyzes the reaction of an acetone compound, for example acetone or diacetone alcohol, with an ammonia donor compound, for example ammonia or 2,2,4,4,6-pentamethyl-1,2,5,6-tetrahydropyrimidine (acetonine).