Organic compounds -- part of the class 532-570 series – Organic compounds – Heterocyclic carbon compounds containing a hetero ring...
Reexamination Certificate
2001-10-02
2003-11-11
Chang, Ceila (Department: 1625)
Organic compounds -- part of the class 532-570 series
Organic compounds
Heterocyclic carbon compounds containing a hetero ring...
C502S263000
Reexamination Certificate
active
06646127
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is directed to a process for the synthesis of 2,2,6,6-tetramethyl-4-oxopiperidine, which is also known as 2,2,6,6-tetramethyl-4-piperidone and triacetonamine. For convenience, the compound will be referred to hereinafter as triacetonamine. More particularly, the present invention is directed to a process that can be carried out at room temperature for the synthesis of triacetonamine with high selectivity by reacting an acetone compound with an ammonia source in the presence of a calcium-containing catalyst.
2. Description of Related Art
Triacetonamine is a known compound that is useful as an intermediate in the preparation of drugs and 2,2,6,6-tetramethyl piperidyl and related light stabilizers for polymeric materials. Its structural formula is:
An outline of how triacetonamine is used as an intermediate in the preparation of stabilizers appears in U.S. Pat. No. 4,124,564.
Triacetonamine has been known at least since the work of Heinz,
Annalen der Chemie,
203:336 (1880). Heinz converted acetone to phorone in about 30% yield and reacted the phorone with ammonia to yield triacetonamine in 70% yield.
Hall,
Journal of the American Chemical Society,
79:5447 (1957) disclosed reacting acetone with ammonia in the presence of calcium chloride for nine days, thereby obtaining a yield of about 20% of triacetonamine after careful fractional distillation.
More specifically, Hall passed ammonia into a mixture of acetone and CaCl
2
for 30 minutes. Additional ammonia was added for 15-minute periods at intervals of 3 hours for five days. After four days of standing at room temperature, the mixture was dark and syrupy, but the calcium chloride had not liquefied. It was poured into 50% NaOH and then the upper layer was decanted from the heavy white sludge of calcium hydroxide, which was then rinsed with ether until tests with ethereal picric acid indicated the absence of amines in the extract. The combined ether layers were dried over K
2
CO
3
and distilled to give a yellow liquid. Careful fractionation of this material through a spinning band column gave 666 g (20.0%) of triacetonamine.
Sosnovsky et al.,
Synthesis
11:735-6 (1976) describe a method for the preparation of triacetonamine in yields of 70-89% (taking into account recovered acetone) from acetone, ammonia, and calcium chloride using easily accessible laboratory equipment.
Wu et al.,
Synthetic Communications
226(19):3565-3569 (1996) describe a method for the preparation of triacetonamine in which p-nitrotoluene is used as a catalyst. Yields of triacetonamine of up to 65% are reported.
Bradbury et al.,
Journal of the Chemical Society,
1394-99 (1947) describe reactions of acetone and ammonia, alone and with a number of different catalysts, that did not give any triacetonamine. Bradbury's product, obtained in 17% yield without catalyst and in 35% to 90% yield depending on catalyst choice, was 2,2,4,4,6-pentamethyl-2,3,4,5-tetrahydropyrimidine hydrate, split to diacetonamine oxalate by the action of alcoholic oxalic acid.
U.S. Pat. No. 1,473,285 discloses the formation of a mixture of acetone amines such as diacetone amine, triacetone diamine, triacetone amine, and other products by the action of ammonia on acetone at high temperatures (100° C.) or at ordinary temperature after long standing. It is disclosed that the use of dehydrating agents such as calcium chloride greatly facilitates the reaction and also gives a product of greater value as an accelerator.
U.S. Pat. No. 3,513,170 discloses a process for the preparation of 2,2-dimethyl-4-oxo-6,6-disubstituted piperidine derivatives which comprises reacting diacetone alcohol with ammonia and a ketone derivative in the presence of a Lewis acid. This patent also discloses a process for the preparation of triacetonamine which comprises reacting 2,2,4,4,6-pentamethyl-2,3,4,5-tetrahydropyrimidine with a Lewis acid in the presence of water. The compounds are said to be useful as intermediates for the synthesis of light stabilizers for polyolefins.
U.S. Pat. No. 3,943,139 discloses the preparation of triacetonamine by heating phorone with aqueous ammonia and basic catalysts, such as lithium, sodium, calcium, or barium hydroxide, in an autoclave under pressure.
U.S. Pat. No. 3,953,459 discloses the preparation of triacetonamine from 2,2,4,4,6-pentamethyl-2,3,4,5-tetrahydropyrimidine by treatment with an acidic catalyst. Suitable catalysts are Lewis acids, protonic acids and their salts with ammonia or organic bases. The reaction may be carried out in organic solvents, preferably in acetone, by gentle heating, for example at 40° to 65° C. Yields of 95% are said to be obtainable after a reaction of several hours.
U.S. Pat. No. 3,959,295 discloses the preparation of triacetonamine from acetone and ammonia in the presence of acidic catalysts. Suitable catalysts are Lewis acids, protonic acids and their salts with ammonia or with organic bases, as for example BF
3
, NH
4
Cl, or H
2
SO
4
. The addition of an alcohol, such as methanol, as well as the use of a cocatalyst may promote the reaction. The process may be carried out in two steps, in the first of which the temperature is held below 35° C. In the second step, a further amount of acetone is added and the temperature is raised to about 40° to 65° C.
U.S. Pat. No. 3,959,298 discloses a process for preparing triacetonamine characterized in that acetonine is reacted with water in the presence of at least 12.5 mole % based on acetonine of an acid catalyst.
U.S. Pat. No. 3,960,875 discloses the preparation of triacetonamine from 2,2,4,4,6-pentamethyl-2,3,4,5-tetramethylpyrimidine (acetonine) by heating in the presence of acetone, diacetone alcohol or water. These reagents may be used in excess or an organic solvent is added. The preferred modification is the heating of acetonine hydrate in an excess of acetone or in an acetone-methanol mixture to about 40° to 65° C. for several hours. The use of diacetone alcohol is said to permit higher reaction temperatures leading to shorter reaction times.
U.S. Pat. No. 3,963,730 discloses a process for preparing triacetonamine, characterized in that acetonine is reacted with acetone in the presence of at least 12.5 mol % based on acetonine of an acid catalyst under anhydrous conditions.
U.S. Pat. No. 4,252,958 discloses a process for preparing triacetonamine 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 acetonine.
U.S. Pat. No. 4,275,211 discloses a process for producing piperidines, including, inter alia, tiacetonamine, wherein a catalyst is used that is a strongly acid ion exchanger having a medium or large mesh size or having large macropores.
U.S. Pat. No. 4,356,308 discloses the synthesis of triacetonamine from acetone and ammonia wherein a partially halogenated or perhalogenated aliphatic or cyclic hydrocarbon is used as catalyst in an amount of from 0.01 to 5 mol %, relative to acetone.
U.S. Pat. No. 4,418,196 discloses process for preparing triacetonamine 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.
U.S. Pat. No. 4,536,581 discloses a process for preparing triacetonamine from ammonia and acetone, wherein acetone and ammonia are reacted in a single stage for a time of 2 to 8 hours in an acetone:ammonia molar ratio of 20:1 to 4:1, at a temperature of 50° to 120° C. and at a pressure of 1 to 50 atmospheres, in the presence of 0.001-0.1 mole of acid catalysts per mole of acetone used in the reaction.
U.S. Pat. No. 4,663,459 discloses a process for the preparation of triacetonamine by reacting acetone with ammonia in the presence of a catalytically effective amount of an organic carboxylic acid halide.
U.S. Pat. No. 4,831,146 discloses a process for producing 2,2,6,6-tetraalkyl-4-oxopiperidines by t
Malz, Jr. Russell E.
Son Young-Chan
Suib Steven L.
Chang Ceila
Reitenbach Daniel
Uniroyal Chemical Company, Inc.
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