US2636052A - Process for the preparation of - Google Patents

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US2636052A
US2636052A US2636052DA US2636052A US 2636052 A US2636052 A US 2636052A US 2636052D A US2636052D A US 2636052DA US 2636052 A US2636052 A US 2636052A
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ionones
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isopropyl
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C49/00—Ketones; Ketenes; Dimeric ketenes; Ketonic chelates
    • C07C49/587—Unsaturated compounds containing a keto groups being part of a ring
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/61—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups
    • C07C45/62—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by hydrogenation of carbon-to-carbon double or triple bonds
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/61—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups
    • C07C45/67—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/61—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups
    • C07C45/67—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton
    • C07C45/68—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton by increase in the number of carbon atoms
    • C07C45/72—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton by increase in the number of carbon atoms by reaction of compounds containing >C = O groups with the same or other compounds containing >C = O groups
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/61—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups
    • C07C45/67—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton
    • C07C45/68—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton by increase in the number of carbon atoms
    • C07C45/72—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton by increase in the number of carbon atoms by reaction of compounds containing >C = O groups with the same or other compounds containing >C = O groups
    • C07C45/74—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton by increase in the number of carbon atoms by reaction of compounds containing >C = O groups with the same or other compounds containing >C = O groups combined with dehydration
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/78—Separation; Purification; Stabilisation; Use of additives
    • C07C45/85—Separation; Purification; Stabilisation; Use of additives by treatment giving rise to a chemical modification
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C49/00—Ketones; Ketenes; Dimeric ketenes; Ketonic chelates
    • C07C49/04—Saturated compounds containing keto groups bound to acyclic carbon atoms
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C49/00—Ketones; Ketenes; Dimeric ketenes; Ketonic chelates
    • C07C49/20—Unsaturated compounds containing keto groups bound to acyclic carbon atoms
    • C07C49/203—Unsaturated compounds containing keto groups bound to acyclic carbon atoms with only carbon-to-carbon double bonds as unsaturation
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C49/00—Ketones; Ketenes; Dimeric ketenes; Ketonic chelates
    • C07C49/385—Saturated compounds containing a keto group being part of a ring
    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12P—FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE
    • C12P7/00—Preparation of oxygen-containing organic compounds
    • C12P7/24—Preparation of oxygen-containing organic compounds containing a carbonyl group
    • C12P7/26—Ketones
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C2601/00—Systems containing only non-condensed rings
    • C07C2601/12—Systems containing only non-condensed rings with a six-membered ring
    • C07C2601/16—Systems containing only non-condensed rings with a six-membered ring the ring being unsaturated

Definitions

  • Patented Apr. 21, 1953 I 1 UNITED STATES PATENT OFFICE PROCESS FOR THE PREPARATION OF 11- AND fi-G-METHYL-IONONES- Heinrich Griitter, BrouggQSwitzerIand, assignor to Genevaich & 00., successeurs de la Soci't Anonyme M. Naef & Cie, Geneva, Switzerland, a corporation of Switzerland No Drawing. Application January 5, 1951, Serial. No. 204,693. In SwitzerlandJanuary 18, 1950 8 Claims. (01. 260-587) 1 2: The present invention has the object of providwith good yields particularly under the influence ing a process for the preparation of aand 13-6- of acidic cyclization agents, this is to say of submethyl-ionones.
  • sulphuric acid may be between 58 to 62%
  • r such as described in Helvetica Chimica Acta 30, The ketoneof the Formula III (which is liquid) 1812 (1947), 32, 1354 (1949) and 33, 2019 (1950)., can exist in.
  • This product as well as the isolated 6-methy1- ionones can be utilized in the perfumery and in the cosmetics industry, wherever a particularly fine violet or orris root fragrance is desired.
  • the process according to the present invention has a marked advantage over the one that consists in the cyclization of the -methyl-pseudoionone, since the synthesis of the iro e is thus found to be shortened and simplified.
  • Example 1 (phosphoric acid used as a cyclization agent) tween 00 and 110 C. under 0.2 mm. Hg) are introduced at such a rate that the temperature does not exceed 0 C.
  • This product is a mixture of various stereoisomers of the airone type and of a few of the fl-irone.
  • the phenyl semi-carbazone melts at 172 0., its 2,4-dinitrophenyl hydrazone at 120 C. These two derivatives are identical with those yielded by the a-lIOIlB. In the mother liquors, stereoisomers may be found.
  • Example 2 (boron trifluoride used as cyclization agent) Into a solution of 15.3 g. of 5-methyl-2-iso-" propyl-1,5,7-decatrienone-9 in 90 cc. of dry benzene cooled to 0 C., a rather rapid flow of BF: is introduced during about 30 minutes while stirring. The reaction manifests itself by a sudden Number increase in temperature which rises to 6-7 C.
  • the absorption of the boron trifiuoride then ceases: amount absorbed 6.3 g.
  • the irone-BFs complex is decomposed by means of 75 cc. of an 8% NaOH solution. The layers formed are separated, washed with 15 cc. of a 25% NaOH solution (while stirring for 1 hour), dried, concentrated and distilled. One obtains 11.7 g. of irone boiling at 83-87 C. under 0.15 mm. Hg. Its constants are:
  • the phenyl semi-carbazone has a melting point of 172 C. which does not show any depression when mixed with that of the Example 1.
  • One part melts below 159 C. and corresponds to difierent stereoisomers.
  • the said various stereoisomers may be first enriched by fractional distillation, and the different fractions then subjected separately to a cyclization producing mixtures containing different quantities of the stereoisomeric G-methyl-alpha-ionones and G-methyl-beta-ionones.
  • a process for the preparation of aand fl-G-methyl-ionones characterized in that 5- methyl-2-isopropyl-1,5,7-decatrienone-9 is subjected to a cyclization by action of an acidic medium which yields conjointly stereoisomeric fi-methyl-a-ionones and S-methyl-fl-ionones.
  • the acidic medium is a medium which if dissolved in nine parts of water would give a 10% solution with a pH less than or equal to 5.
  • a process according to claim 3 characterized in that the said agent is sulphuric acid of a density between 1.49 and 1.53 (58-62%) -'7.
  • a process according to claim 4 characterized in that the said agent is phosphoric acid of a .the stereoisomeric 5-1nethyl-2-isopropyl-1,5,7- decatrienones-Q to be cyclised or selected accord- ,ing to boiling point and then subjected to a cyclization yielding a mixture of stereoisomeric 6-methyl-a-ionones and G-methyl-B-ionones.

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Description

Patented Apr. 21, 1953 I 1 UNITED STATES PATENT OFFICE PROCESS FOR THE PREPARATION OF 11- AND fi-G-METHYL-IONONES- Heinrich Griitter, BrouggQSwitzerIand, assignor to Firmenich & 00., successeurs de la Soci't Anonyme M. Naef & Cie, Geneva, Switzerland, a corporation of Switzerland No Drawing. Application January 5, 1951, Serial. No. 204,693. In SwitzerlandJanuary 18, 1950 8 Claims. (01. 260-587) 1 2: The present invention has the object of providwith good yields particularly under the influence ing a process for the preparation of aand 13-6- of acidic cyclization agents, this is to say of submethyl-ionones. stances whichwhen admixed solely to water, form This process is characterized in that 5-methylliquids the pH value of which is lower than 5. 2-isopropy1-1,5,7-decatrienone-9 is subjected to 5 Amongst these cyclization agents, sulphuric acid a cyclization which yields conjointly stereo- (-60%), phosphoric acid (-83%) and boron triisomeric 6-methyl-a-ionones and 6-methyl-fifluoride give the best results. The concentration ionones. of the. sulphuric acid may be between 58 to 62% The 5-methyl-2-isopropyl-1,5,7-decatrienone-9, (density 1.49 to 1.53), and the phosphoric acid I Eb.0.03 mm. 110-115; (1 :0394; n 2 =1.5225 10 may be of 80 to 87% concentration (density becan easily be synthesized by standard methods, tween 1.65 and. 1.7). r such as described in Helvetica Chimica Acta 30, The ketoneof the Formula III (which is liquid) 1812 (1947), 32, 1354 (1949) and 33, 2019 (1950)., can exist in. four different stereoisomeric forms in which the starting material dimethylheptenone owing to its double bonds at the carbon atoms 5 is exchanged for 2-isopropyl-hexene-l-one-5 and 7.. The commercial product obtained by (Formula II), a product obtainable without difsynthesis is, however, a mixture in which one of ficulty from thujone, for example, according to the isomers may be more or less predominant Wallach (Annalen 275, 174 (1893), Berichte 30, according to the boiling point of the fraction 440 (1897), Simonsen, The Terpenes,"vol. 11, page utilized. The cyclization of this mixture yields 37, Second Edition). the aand 5-6-methylionones which are, in turn,
It will now be indicated diagrammatically how mixtures of stereoisomers. The relative proporthis starting ketone can be prepared and how by tions of the latter depend on the stereoisomerism cyclization it yields conjointly the aand 8-6- of the starting ketone but it is also possible that methyl-ionones (Formulae IV and V, respecthey are influencedat least partly, by the conditively): tions in which the cyclization is carried out.
CH3 CH3 0% CH3 CH3 CH3 CH1 CH2 C CH2 10 CH 0112 9 CH; 0 C o on (5H a EIz CO-OH3 3:11, i so Cfi cn Ca CH s GHa.
I II III 1 CH3 CH3 CH3 CH3 on, 0 CH 0113 C on" ofi o \CH "ofi o on H. t to te. t o
0% \CH3 \CH3 cfiz CHa CHa IV v Nothin could make one expect hitherto that The direct product of the process according to a substance like the ketone of the Formula III the invention is a mixture of stereoisomers of the would cyclize according to the above scheme. In G-methyI-a-ionone and of the G-methyI-fl-ionone. fact, contrary to all known examples (cyclization 60 It does not difier or differs but little as regards of pseudo-ionone, pseudo-irone, etc.), the 1' carits properties from the one obtained by the procbon atom which takes part directly in the cyclizaess described in U. S. patent application Serial tion of the process according to the invention is No. 778,752 of October 9, 1947. The stereoisonot adjacent to a double bond. In spite of this, mers of either the fi-methyl-a-ionone or of the the ketone of the Formula III cyclizes readily and G-methyl-B-ionone can be isolated from this di.
rect product as described in the said U. S. patent application.
This product, as well as the isolated 6-methy1- ionones can be utilized in the perfumery and in the cosmetics industry, wherever a particularly fine violet or orris root fragrance is desired.
Owing to the fact that the -methyl-2-isopropyl-1,5,7-decatrienone-9 (Formula III) used as a starting material can be readily synthesized, the process according to the present invention has a marked advantage over the one that consists in the cyclization of the -methyl-pseudoionone, since the synthesis of the iro e is thus found to be shortened and simplified.
It will now be described how the process according to the present invention can be carried out in practice:
Example 1 (phosphoric acid used as a cyclization agent) tween 00 and 110 C. under 0.2 mm. Hg) are introduced at such a rate that the temperature does not exceed 0 C. The solution is maintained subsequently at 0 C. for 20 minutes, then heated to between and C, and maintained 15 more minutes at this temperature. It is mechanically agitated during the whole period of the operation. It is then poured on ice, extract- Prior to purification, the irone has often a lower density (d4 minimum=0.930).
This product is a mixture of various stereoisomers of the airone type and of a few of the fl-irone. The phenyl semi-carbazone melts at 172 0., its 2,4-dinitrophenyl hydrazone at 120 C. These two derivatives are identical with those yielded by the a-lIOIlB. In the mother liquors, stereoisomers may be found.
Example 2 (boron trifluoride used as cyclization agent) Into a solution of 15.3 g. of 5-methyl-2-iso-" propyl-1,5,7-decatrienone-9 in 90 cc. of dry benzene cooled to 0 C., a rather rapid flow of BF: is introduced during about 30 minutes while stirring. The reaction manifests itself by a sudden Number increase in temperature which rises to 6-7 C.
The absorption of the boron trifiuoride then ceases: amount absorbed 6.3 g. The irone-BFs complex is decomposed by means of 75 cc. of an 8% NaOH solution. The layers formed are separated, washed with 15 cc. of a 25% NaOH solution (while stirring for 1 hour), dried, concentrated and distilled. One obtains 11.7 g. of irone boiling at 83-87 C. under 0.15 mm. Hg. Its constants are:
This is a mixture of divers stereoisomers of the a-irone type and of a few of the B-irone. The phenyl semi-carbazone has a melting point of 172 C. which does not show any depression when mixed with that of the Example 1. One part melts below 159 C. and corresponds to difierent stereoisomers.
Instead of submitting to the cyclization mixtures of the various stereoisomers of the 5- methyl-Z-isopropyl-1,5,7-decatrienone-9, the said various stereoisomers may be first enriched by fractional distillation, and the different fractions then subjected separately to a cyclization producing mixtures containing different quantities of the stereoisomeric G-methyl-alpha-ionones and G-methyl-beta-ionones.
What I claim is:
1. A process for the preparation of aand fl-G-methyl-ionones, characterized in that 5- methyl-2-isopropyl-1,5,7-decatrienone-9 is subjected to a cyclization by action of an acidic medium which yields conjointly stereoisomeric fi-methyl-a-ionones and S-methyl-fl-ionones.
2. A process according to claim 1, in which the acidic medium is a medium which if dissolved in nine parts of water would give a 10% solution with a pH less than or equal to 5.
3. A process according to claim 2, characterized in that the said agent is sulphuric acid.
4. A process according to claim 2, characterized in that the said agent is phosphoric acid.
5. A process according to claim 2, characterized in that the said agent is boron trifluoride.
, 6. A process according to claim 3, characterized in that the said agent is sulphuric acid of a density between 1.49 and 1.53 (58-62%) -'7. A process according to claim 4, characterized in that the said agent is phosphoric acid of a .the stereoisomeric 5-1nethyl-2-isopropyl-1,5,7- decatrienones-Q to be cyclised or selected accord- ,ing to boiling point and then subjected to a cyclization yielding a mixture of stereoisomeric 6-methyl-a-ionones and G-methyl-B-ionones.
HEINRICH GRIITTTER.
References Cited in the file of this patent UNITED STATES PATENTS Name Date 2,517,800 Naves Aug. 8, 1950 FOREIGN PATENTS Number Country Date 262,269 Switzerland Oct. 1, 1949 Simonsen, The Terpenesfif vol. II, pp. 37 and 38, 2d ed., pub. 1949 by Cambridge University Press.

Claims (1)

1. A PROCESS OF THE PREPARATION OF A- AND B-6-METHYL-IONOSES, CHARACTERIZED IN THAT 5METHYL-2-ISOPROPYL-1,5-7-DECATRIENON-9 IS SUBJECTED TO A CYCLIZATION BY ACTION OF AN ACIDIC MEDIUM WHICH YIELDS CONJOINTLY STEREOISOMERIC 6-METHYL-A-IONONES AND 6-METHYL-B-IONONES.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2877271A (en) * 1957-11-27 1959-03-10 Hoffmann La Roche Preparation of ionones by cyclization of pseudoionones with sulfuric acid
US3019265A (en) * 1959-04-02 1962-01-30 Givaudan Corp Process for preparing irones
US3897370A (en) * 1971-04-26 1975-07-29 Dragoco Gerberding Co Gmbh Aroma compositions containing cycloaliphatic crotonyl compounds

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH262269A (en) * 1946-10-21 1949-06-30 Firmenich & Cie Successeurs De Process for the preparation of 6-methyl-a-ionone.
US2517800A (en) * 1948-05-04 1950-08-08 Givaudan Corp Process for preparing alpha-irone isomers by cyclization of pseudoirones

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH262269A (en) * 1946-10-21 1949-06-30 Firmenich & Cie Successeurs De Process for the preparation of 6-methyl-a-ionone.
US2517800A (en) * 1948-05-04 1950-08-08 Givaudan Corp Process for preparing alpha-irone isomers by cyclization of pseudoirones

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2877271A (en) * 1957-11-27 1959-03-10 Hoffmann La Roche Preparation of ionones by cyclization of pseudoionones with sulfuric acid
US3019265A (en) * 1959-04-02 1962-01-30 Givaudan Corp Process for preparing irones
US3897370A (en) * 1971-04-26 1975-07-29 Dragoco Gerberding Co Gmbh Aroma compositions containing cycloaliphatic crotonyl compounds

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