Process for the preparation of 2,2,6,6-tetramethyl-4-oxopiperidine
AssigneeICI Americas Inc.
InventorsWalter M. Kruse, John F. Stephen
Life of this patent
Estimating the term…
Abstract
2,2,6,6-tetramethyl-4-oxopiperidine is prepared from acetone and ammonia in the presence of catalytic amounts of active halogen compounds selected from sulfonylhalides, sulfurylhalides, N-haloamides, N-haloimides, .beta.-haloesters, .alpha.-haloketones, .alpha.-halohydroxy compounds, and .beta.-halonitriles.
Claims2
In a process for the preparation of 2,2,-6,6-tetramethyl-4-oxopiperidine which comprises reacting acetone with ammonia at temperatures ranging from 5.degree. -70.degree. C. the improvement which comprises carrying out said reaction in the presence of catalytic amounts of active halogen compounds selected from those in the group consisting of SO.sub.2 X.sub.2, R--SO.sub.2 X, RCO--N(X)--COR, RCO(NHX), RCH(X)CH.sub.2 --CO.sub.2 R, RCH(X)CH.sub.2 --CN, RCH(OH)--CH.sub.2 X, and RCO--CH.sub.2 (X) wherein X is chlorine or bromine and R is a group selected from alkyl, aryl, arylalkyl and alkylaryl groups having up to 22 carbon atoms wherein acetone is first reacted with ammonia in concentrations of 0.5-1.5 mol NH.sub.3 per mol acetone at temperatures in the range of 5.degree.-30.degree. C., and there after with additional acetone in concentrations of 5-10 mols ace tone per mol NH.sub.3 at temperatures of 50.degree.-70.degree. C.
A process for the preparation of 2,2,6,6-tetramethyl-4-oxopiperidine which comprises reacting acetone with ammonia at temperatures ranging from 5.degree.-70.degree. C., the improvement which comprises carrying out said reaction in the presence of catalytic amounts of active halogen compounds selected from the group consisting of tetrachloro-1,- 4-benzoquinone, methanesulfonylchloride, sulfurylchloride, 1,3-dibromo-5,5-dimethylhydantoin, 1,3-dichloro-5,5-dimethylhydantoin, N-bromosuccinimide, trichloromelamine, trichloroisocyanuric acid, 3-chloropropionitrile, ethyl-3-chloropropionate, 1,3-dichloro-2-propanol, and N-chlorosuccinimide and their chloro or bromo equivalents wherein acetone is first reacted with ammonia in concentration of 0.5-1.5 mol ammonia per mol acetone at temperatures in the range of 5.degree.-30.degree. C., and thereafter with additional acetone in concentrations of 5-10 mols acetone per mol ammonia at temperatures of 50.degree.-70.degree. C.
Dependencies are inferred from the claim text.