ES259646A1 - Process for preparing l- -aminolactam from a mixture of d-and l- -aminolactam - Google Patents
Process for preparing l- -aminolactam from a mixture of d-and l- -aminolactamInfo
- Publication number
- ES259646A1 ES259646A1 ES0259646A ES259646A ES259646A1 ES 259646 A1 ES259646 A1 ES 259646A1 ES 0259646 A ES0259646 A ES 0259646A ES 259646 A ES259646 A ES 259646A ES 259646 A1 ES259646 A1 ES 259646A1
- Authority
- ES
- Spain
- Prior art keywords
- aminolactam
- salt
- carboxylic acid
- liquid medium
- pyrrolidone carboxylic
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D223/00—Heterocyclic compounds containing seven-membered rings having one nitrogen atom as the only ring hetero atom
- C07D223/02—Heterocyclic compounds containing seven-membered rings having one nitrogen atom as the only ring hetero atom not condensed with other rings
- C07D223/06—Heterocyclic compounds containing seven-membered rings having one nitrogen atom as the only ring hetero atom not condensed with other rings with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D223/12—Nitrogen atoms not forming part of a nitro radical
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Pyrrole Compounds (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
Racemic a -aminolactams are resolved by forming a precipitate containing only or primarily either D-or L-a -aminolactam as the salt of the optically active pyrrolidone carboxylic acid with the same steric configuration, such precipitation being effected in a liquid medium in which the salt of both D-and L-a -aminolactam with the said acid are insoluble or substantially insoluble, using the pyrrolidine carboxylic acid as such or as ammonium pyrrolidonate and in such smaller amount than that which is equivalent to the total amount of a -aminolactam that all or most of one of the optical antipodes of the said mixture remains in the liquid phase. The optically-active a -aminolactams are subsequently separated from their salts with the pyrrolidone carboxylic acid. The liquid medium used for the resolution is preferably dioxane or a hydrocarbon. Both the a -aminolactam and the pyrrolidone carboxylic acid may be added to the liquid medium of the process as solutions in a polar solvent, such as water or an alcohol, and this polar solvent is preferably expelled from the liquid medium at the same rate as it is added, e.g. by means of azeotropic distillation. When L-pyrrolidone carboxylic acid or its ammonium salt is used for resolution, the preferred amount is not more than 1 mole for mole of L-a -aminolactam. The precipitate is then predominantly L, L-salt, and this may be taken up in a polar solvent and treated with an amount of L-a -aminolactam which is at least equivalent to the amount of D-a -aminolactam occurring as a L, D-salt contaminant in the L, L-salt. The solution of L, L-salt in a polar solvent is then added to a further amount of the liquid medium used in the process, and pure L, L-salt is precipitated by expelling the polar solvent. The L, L-salt may be passed as an aqueous solution over a cation exchanger in the ammonium form. L-pyrrolidone carboxylic acid passes through as the ammnoium salt and may be used again for the resolution step, while L-a -aminolactam may be recovered by subsequent elution with aqueous ammonia. The original mother liquor containing mainly D-a -aminolactam may be racemized for re-use by heating it with sodium or anhydrous caustic soda. When D-pyrrolidone carboxylic acid or its ammonium salt is used for resolution, the preferred amount is at least 1 mole per mole of D-a -aminolactam present. The precipitate is then predominantly D,D-salt, from which D-a -aminolactam may be recovered using an ion exchanger as before. The recovered D-a -aminolactam is then dissolved in fresh liquid medium and racemized for re-use by heating it with anhydrous caustic soda. The original mother liquor containing mainly L-a -aminolactam may be subsequently evaporated to yield the required product. The processes described above may be adapted for continuous working. Specified starting materials are racemic a -aminocaprolactam, a -aminovalerolactam and a -amino-oenantholactam. Specification 884,299 is referred to.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NL241310 | 1959-07-15 |
Publications (1)
Publication Number | Publication Date |
---|---|
ES259646A1 true ES259646A1 (en) | 1960-12-16 |
Family
ID=19751831
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
ES0259646A Expired ES259646A1 (en) | 1959-07-15 | 1960-07-14 | Process for preparing l- -aminolactam from a mixture of d-and l- -aminolactam |
Country Status (8)
Country | Link |
---|---|
BE (1) | BE593068A (en) |
CH (1) | CH391709A (en) |
DE (1) | DE1445149A1 (en) |
ES (1) | ES259646A1 (en) |
FI (1) | FI40542B (en) |
GB (1) | GB954207A (en) |
LU (1) | LU38944A1 (en) |
SE (1) | SE301808B (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL6606261A (en) * | 1966-05-07 | 1967-11-08 |
-
1960
- 1960-07-12 GB GB2428560A patent/GB954207A/en not_active Expired
- 1960-07-13 SE SE687060A patent/SE301808B/xx unknown
- 1960-07-13 LU LU38944D patent/LU38944A1/xx unknown
- 1960-07-14 DE DE19601445149 patent/DE1445149A1/en active Pending
- 1960-07-14 ES ES0259646A patent/ES259646A1/en not_active Expired
- 1960-07-14 CH CH805160A patent/CH391709A/en unknown
- 1960-07-15 BE BE593068A patent/BE593068A/en unknown
- 1960-07-15 FI FI121060A patent/FI40542B/fi active
Also Published As
Publication number | Publication date |
---|---|
DE1445149A1 (en) | 1969-01-23 |
FI40542B (en) | 1968-11-30 |
BE593068A (en) | 1960-10-31 |
CH391709A (en) | 1965-05-15 |
GB954207A (en) | 1964-04-02 |
LU38944A1 (en) | 1960-10-08 |
SE301808B (en) | 1968-06-24 |
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