US4078008A
Expired / Lapsed
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Process for the preparation of dienes
Assignee: Bayer AG
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Filing: 1976-07-22
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Granted: 1978-03-07
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Expires: 1996-07-22
Abstract
Abstract A process for the preparation of a diene of the formula ##STR1## in which X and Y are independently fluorine, chlorine or bromine Which comprises contacting a 1,1,1-trihalo-4-methyl-4-hydroxypentane of the formula ##STR2## in which X and Y have the previously assigned significance and Z is a chorine or bromine atom With a dehydrohalogenating agent and a dehydration agent.
Inventors
- 👤 Reinhard Lantzsch
- 👤 Dieter Arlt
- 👤 Ernst Kysela
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 00:14
CPC Classifications
C; C07; C07C; C07C17/00; C07C17/35; C07C17/25
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
60 words
A process for the preparation of a diene of the formula ##STR7## wherein X and Y are independently fluorine, bromine or chlorine which comprises contacting a 1,1,1-trihalo-4-methyl-4-hydroxy-pentane of the formula ##STR8## wherein X and Y have the previously assigned significance and Z is chlorine or bromine with a dehydrohalogenation agent and a dehydration agent under respectively dehydrohalogenation and dehydration conditions.
Claim 2
Dependent Claim
60 words
A process for the preparation of a diene of the formula ##STR7## wherein X and Y are independently fluorine, bromine or chlorine which comprises contacting a 1,1,1-trihalo-4-methyl-4-hydroxy-pentane of the formula ##STR8## wherein X and Y have the previously assigned significance and Z is chlorine or bromine with a dehydrohalogenation agent and a dehydration agent under respectively dehydrohalogenation and dehydration conditions.
Claim 3
Dependent Claim
30 words
A process according to claim 1 wherein said pentane is initially contracted with a dehydrohalogenation agent and following dehydrohalogenation thereof is contacted with a dehydration agent to eliminate water therefrom.
Claim 4
Dependent Claim
29 words
A process according to claim 1 wherein said pentane is initially contacted with a dehydration agent and thereafter is contacted with a dehydrohalogenation agent to eliminate hydrogen halide therefrom.
Claim 5
Dependent Claim
16 words
A process according to claim 1 wherein said dehydrohalogenation agent is a basic acid binding agent.
Claim 6
Dependent Claim
17 words
A process according to claim 4 wherein said basic acid binding agent is an alkali metal alcoholate.
Claim 7
Dependent Claim
25 words
A process according to claim 1 wherein said alkali metal alcoholate is selected from the group consisting of sodium methylate, sodium ethylate and potassium tert.-butylate.
Claim 8
Dependent Claim
17 words
A process according to claim 4 wherein the basic acid binding agent is an alkali metal hydroxide.
Claim 9
Dependent Claim
72 words
A process according to claim 1 wherein the dehydrohalogenation agent is selected from the group consisting of a salt of a metal of the Second Main Group of the Periodic Table, a salt of a metal of the Third Main Group of the Periodic Table, a salt of a metal of the Second Sub-Group of the Periodic Table and a salt of a metal of the Eighth Sub-Group of the Periodic Table.
Claim 10
Dependent Claim
28 words
A process according to claim 8 wherein said dehydrohalogenation agent is selected from the group consisting of calcium chloride, barium chloride, zinc chloride, aluminum chloride and iron-III chloride.
Claim 11
Dependent Claim
23 words
A process according to claim 1 wherein the dehydrohalogenation agent is present in the reaction mixture in an amount of 0.5-10% by weight.
Claim 12
Dependent Claim
23 words
A process according to claim 10 wherein the dehydrohalogenation agent is present in the reaction mixture in the amount of 1-25% by weight.
Claim 13
Dependent Claim
25 words
A process according to claim 10 wherein the dehydrohalogenation is effected with a basic acid binding agent at a temperature between 50° and 150° C.
Claim 14
Dependent Claim
79 words
A process according to claim 1 wherein dehydrohalogenation is effected at a temperature between 50° and 300° C employing a dehydrohalogenation agent which is a salt of a metal of the Second Main Group of the Periodic Table, a salt of a metal of the Third Main Group of the Periodic Table, a salt of a metal of the Second Sub-Group of the Periodic Table or a salt of a metal of the Eighth Sub-Group of the Periodic Table.
Claim 15
Dependent Claim
72 words
A process according to claim 1 wherein the dyhydration agent is selected from the group consisting of an acid salt of an inorganic acid, a neutral salt, an amine salt, a carboxylic acid, a carboxylic acid anhydride, iodine, an acid ion exchanger, a salt of a metal of the Second and Third Main Groups or the Second and Eighth Sub-Groups of the Periodic Table, iodine, a sulfonic acid and a metal oxide.
Claim 16
Dependent Claim
23 words
A process according to claim 14 wherein the dehydration agent is present in the reaction mixture in an amount of 0.5-100% by weight.
Claim 17
Dependent Claim
25 words
A process according to claim 14 wherein the dehydration agent is present in the reaction mixture in an amount of 1 to 25% by weight.
Claim 18
Dependent Claim
56 words
A process according to claim 14 wherein the dehydration agent is selected from the group consisting of potassium bisulfate, sodium bisulfate, magnesium sulfate, iodine, phosphoric acid, oxalic acid, formic acid, acetic acid, acetic anhydride, phthalic anhydride, p-toluene sulfonic acid, aluminum oxide, zirconium-IV oxide, thorium oxide, calcium chloride, barium chloride, zinc chloride, aluminum chloride and iron-III chloride.
Claim 19
Dependent Claim
19 words
A process according to claim 14 wherein the dehydration is effected at a temperature between 20° and 300° C.
Claim 20
Dependent Claim
19 words
A process according to claim 18 wherein the dehydration is effected at a temperature between 50° and 225° C.
Claim 21
Dependent Claim
11 words
A process according to claim 1 wherein said pentane is 1,1,1-trichloro-4-methyl-4-hydroxypentane.
Claim 22
Dependent Claim
45 words
A process according to claim 1 wherein the dehydrohalogenation agent is selected from the group consisting of the salt of a metal of the Second Main Group of the Periodic Table and a salt of a metal of Third Main Group of the Periodic Table.
Claim 23
Dependent Claim
46 words
A process according to claim 2 wherein the dehydrohalogenation agent is selected from the group consisting of a salt of a metal of the Second Main Group of the Periodic Table and a salt of a metal of the Third Main Group of the Periodic Table.
Claim 24
Dependent Claim
25 words
A process according to claim 2 wherein said dehydrohalogenation agent is selected from the group consisting of sodium methylate, sodium ethylate and potassium tert butylate.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-03-06 | 1981-09-05 | 1982-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-03-06 | 1985-09-05 | 1986-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-03-06 | 1989-09-05 | 1990-03-07 | $7700.00 | Window Closed / Lapsed |