Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D327/00—Heterocyclic compounds containing rings having oxygen and sulfur atoms as the only ring hetero atoms
  • C07D327/10—Heterocyclic compounds containing rings having oxygen and sulfur atoms as the only ring hetero atoms two oxygen atoms and one sulfur atom, e.g. cyclic sulfates

Definitions

• Propanesultone is stabilized by adding at least one compound selected from the group consisting of aliphatic amines, alicyclic amines, aralkylamines, non-aromatic cyclic amines, N-alkyl-substituted aromatic amines, aminoalcohols, amine character nitrogen containing carboxylic acids having 2 to carbon atoms and their esters, amides, pyridines, quinolines, and reaction products of these compounds with propanesultone.
• the present invention relates to a process for stabilizing the hue of propanesultone.
• Propanesultone is a colorless liquid or crystal having a melting point of 31 C.
• This compound is an important synthetic material used widely as an agent for improving the dye-ability of synthetic fibers, as a surfactant, as an additive for modified starch, etc.
• propanesultone becomes colored gradually to light yellow or, in extreme cases, to orange or reddish brown during storage and transportation at ambient temperature, or under heating, so that its commercial value is reduced. Although the prevention of coloring of propanesultone has been long sought, a satisfactory process for doing so has not been found yet.
• the object of the invention is to provide a process for stabilizing propanesultone by adding one or more of said stabilizer compounds to propanesultone to inhibit coloring and deterioration of propanesultone at ambient temperature or at an elevated temperature for a long period of time.
• Aliphatic amines Primary amines (RNHZ), secondary amines (RR'NH) and tertiary amines (RRR"N), in which R, R and R" each is alkyl having 1 to 20 carbon atoms, or allyl, such as mono-, diand tri-ethylamine, n-propylamine, isopropylamine, n-butylamine, etc.
• Alicyclic amines Primary, secondary or tertiary amines, as set forth in (a), in which one of the R groups is a saturated ring having from 3 to 7 carbon atoms in v the ring and which may be substituted on the ring by hydrocarbons, such as cyclohexylamine, methylcyclohexylamine, etc.
• Aralkylamines Amines as set forth in (a), in which one of the R groups is (Ar) (Alk), wherein Ar is phenyl and Alk is an alkylene group of 1 to 6 carbon atoms, such as benzylamine phenethylamine, etc.
• Non-aromatic cyclic amines Cyclic compounds containing in the ring at least 1 nitrogen atom, such as pyrrolidine, morpholine, piperidine, piperazine, hexamethylenetetraamine, melamine, etc.
• N-alkyl substituted aromatic amines Compounds of the formula ArNR R wherein Ar is phenyl or phenyl substituted with a hydrocarbon group, at least one of R and R is alkyl having from 1 to -6 carbon atoms and the other of R and R is alkyl having 1 to 6 carbon atoms or H, such as N-methylaniline and N,N-dimethylaniline, etc.
• Aminoalcohols Compounds according to (a), in which at least one of R, R and R" is substituted with OH, such as mono-, diand tri-ethanolamine, propanolamine, 2-amino-2-methylpropanol-(1), etc.
• Amine character nitrogen containing carboxylic acids having 2-10 carbon atoms and their esters Nitrilotriacetic acid, nicotinic acid, methyl nicotinate, methyl picolinate, etc.
• Pyridines Pyridine and pyridine substituted on the ring with alkyl groups having 1 to 6 carbon atoms, such as pyridine, picoline, (0;,3, or Z-methyl-S-ethylpyridine, etc.
• Quinolines Quinoline and quinoline substituted on the ring with alkyl groups having 1 to 6 carbon atoms, such as quinoline, methylquinoline, etc.
• the stabilized propanesultone composition of the present invention may be obtained easily by directly adding and dissolving or partially dissolving the stabilizer or stabilizers in liquid propanesultone.
• the preferred amount of the stabilizer added to propanesultone is 0.01-1% by weight, based on the weight of the propanesultone treated. If necessary, two or more stabilizers may be used together in the process of the present invention.
• the most preferred direct method of evaluating the stability of propanesultone or the stabilizing elfect of the stabilizer for propanesultone comprises allowing a sample to stand under ordinary storage conditions for a long period of time and determining the color change that occurs.
• this method is inconvenient, because it requires a long period of time for the evaluation. Therefore, the stabilizing eifects were compared according to an accelerated coloring test under the following special conditions.
• Accelerated coloring test under heating Thirty (30) grams of propanesultone sample were charged into a hard glass ampoule, which was then closed by fusion. The ampoule was allowed to stand at C. for a predetermined period of time. The hue of the sample was determined by measuring the Gardner number or APHA number thereof.
• Example 1 Samples were prepared by mixing freshly prepared propanesultone (hue: Gardner No. 1, purity: about 99%) with 0.1 wt. percent of each of the stabilizers listed in Table 1 and were subjected to an accelerated coloring test under heating. For comparison, propanesultone containing no stabilizer and propanesultone containing the same amount of representative phenolic stabilizers were tested in the same manner. The results are shown in Table 1. The numerical values in the Table are Gardner numbers. The heating was effected in all cases at 120 C. for 90 minutes.
• Cyclohexylamine 3 4-Methylcyclohexylamine 3 Aralkylamines:
• Example 4 Accelerated coloring tests were carried out previously to obtain some samples of propanesultone, the hues of which were dilferent from one another. The samples were vmixed with 0.1 wt. percent of (1) triethanolamine and (2) pyridine and were allowed to stand at room temperature for 200 days and the degrees of coloring were examined at the intervals stated in the following table. In the samemanner, propanesulfone containing noa'dditive was also tested as a control. The results are shown in Table 4. The numerical values in the Table are APHA numbers.
• triethanolamine and pyridine both have an excellent stabilization effect, i.e., an effect of preventing coloring of propanesultone samples of a wide range of quality.
• the formed crystals were washed with methleast one nitrogen atom selected from the group pyranol repeatedly to remove unreacted substances and then rolidine, morpholine, piperidine, piperazine, N,N'- they were drled under a reduced'nressure- 45 dimethyl piperazine, hexamethylenetetraamine and Samples were prepared by mixing freshly prepared promelamine; panesultone (11,116: Gardner Q- Punty: above 99%) e.
• Aliphatic amines Triethylamine n-Hexane White turbid paste 4 4 3 (b)- Alicyclic amines Cyclohexylamine Methanol-.. White powder.-... 3 4 8 (c) Ara1ky1amines Benzylamine Diethyl ether. White crystal--- 4 2 (d). Non-aromatic cyclic amines..- N,N-dimethyl piperazine.-- Methanol Yellow powder- 3 4 2 (e) N-alkyl substituted aromatic N,N-dimethyl aniline Acetone White powder 3 4 3 1188. (1).. A i n oaicohols Triethanolamine. Methanol do 3 3.5 2 (g).
• amides selected from the group formamide, dimethylformamide, acetamide, acrylamide, p-toluenesulfonabout 0.01 to 1% by Weight, based on the weight of pro- 10 panesultone, of at least one stabilizer compound selected from the group consisting of a. primary amines RNH secondary amines RR'NH and tertiary amines RR'R"N, in which R, R and R" each is alkyl having 1 to 20 carbon atoms, or allyl;
• amide nicotinic acid amide, a-pyrrolidone and ecaprolactam
• pyridine and pyridines substituted on the ring with b. primary, secondary or tertiary amines, as set forth 15 alkyl groups having 1 to 6 carbon atoms;
• one of the R groups is a saturated ring j.
• quinoline and quinolines substituted on the ring having from 3 to 7 carbon atoms in the ring and with alkyl groups having 1 to 6 carbon atoms; which can be substituted on the ring by methyl k. reaction products of the above compounds a through radicals; 20 j with propanesultone.
• amines as set forth in a, in which one of the R groups is (Ar) (Alk)-, wherein Ar is phenyl and Alk is References Cited an alkylene group of 1 to 6 carbon atoms; UNITED STATES PATENTS d. non-aromatic cyclic amines containing in the ring at least one nitrogen atom selected from the group pyr- 25 3,479,352 11/1969 Norell 260-2934 rolidine, morpholine, piperidine, piperazine, N,N'-dimethyl piperazine, hexamethylenetetraamine and melamine;

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Hydrogenated Pyridines (AREA)
• Pyridine Compounds (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=11931875

Family Applications (1)

Country Status (6)

Cited By (3)

• 1972
  • 1972-03-22 IT IT22297/72A patent/IT950689B/it active
  • 1972-03-22 DE DE19722213933 patent/DE2213933A1/de active Pending
  • 1972-03-22 US US00236994A patent/US3829438A/en not_active Expired - Lifetime
  • 1972-03-23 GB GB1360172A patent/GB1380824A/en not_active Expired
  • 1972-03-23 FR FR727210150A patent/FR2130581B1/fr not_active Expired
  • 1972-03-24 NL NL7203957A patent/NL7203957A/xx not_active Application Discontinuation

Also Published As

Similar Documents