A-Alkoxy-4,4-Dioxy-Polyalkyl-Piperidines as Radical Polymerization Inhibitors

Assignee Ciba Specialty Chemicals Corp. (Tarrytown, NY) 

Free radical polymerization inhibitors have been prepared by reacting tetramethylpi-peridive oxyl derivatives with selected glycidyl intermediates. When used as a styrene polymerization regulator in 1.0mol% and 0.1mol% at 120°C, molecular weights of 2400 and 43,400 daltons, respectively, were obtained. 

Preparation of 7,7,9,9-Tetramethyl-8-[l-(4-Oxiranylmethoxy-Phenyl)-Ethoxy]-l,4-Dioxa-8-Aza-Spiro[4.5]Decan 

A mixture of 7,7,9,9-tetramethyl-l,4-dioxa-8-aza-spiro [4.5] decan-8-oxyl (50 g) and 2-(4-ethylphenoxymethyl)oxrran (124.75 g) was heated to 60°C and then treated with of 0.32 g of copper(II) chloride dissolved in 1.6 ml of ethanol. This mixture was further treated with the dropwise addition of 70% aqueous t-butylhydroperoxide (45 g), reacted for 16 hours at 60°C, and cooled to ambient temperature. Excess t-butyUiydroperoxide was decomposed by the dropwise addition of 20% aqueous sodium pyrosulfite solution. The mixture was then treated with 100 ml of EtOAc, and the organic and aqueous phases were separated. The organic 

TABLE 1. Experimental A-alkoxy-4,4-dioxy-polyalkyl-piperidine regulators and corresponding melting points. 

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Title A -Alkoxy-4,4-Dioxy-Polyalkyl-Piperidines as Radical Polymerization Inhibitors... 

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