US4288369A
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Production of cyclic ethers
Assignee: Western Kentucky University
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Filing: 1979-08-31
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Granted: 1981-09-08
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Expires: 1999-08-31
Abstract
Abstract A process for the preparation of cyclic ethers which comprises reacting an alkanediol in which the hydroxyl groups are separated by a chain of at least four carbon atoms in the liquid phase of a catalyst comprising a palladium salt and a copper salt, and recovering the cyclic ether thus formed by a separation step such as distillation. The reaction is carried out in a molecular oxygen gaseous atmosphere. A preferred catalyst is palladium chloride in combination with a copper salt such as cupric chloride or cupric nitrate.
Inventors
- 👤 Norman L. Holy
- 👤 Theodore E. Nalesnik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 20:08
CPC Classifications
C; C07; C07D; C07D313/00; C07D313/02; C07D313/04; C07D307/00; C07D307/02; C07D307/04; C07D307/06; C07D307/08; C07D309/00; C07D309/02; C07D309/04
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
100 words
A process for the preparation of an unsubstituted cyclic ether which comprises reacting an unsubstituted alkanediol in which the hydroxyl groups are separated by a chain of at least four carbon atoms in the liquid phase, in a molecular oxygen gaseous atmosphere, at a temperature of from about 150° C. to 300° C. in the presence of a catalytic amount of a catalyst comprising about 0.45 to 0.71 grams of palladium in a palladium salt, about 0.30 to 1.2 grams of copper in a copper salt and about 0.30 to 1.1 grams of chloride ion, all per mole of alkanediol.
Claim 2
Dependent Claim
100 words
A process for the preparation of an unsubstituted cyclic ether which comprises reacting an unsubstituted alkanediol in which the hydroxyl groups are separated by a chain of at least four carbon atoms in the liquid phase, in a molecular oxygen gaseous atmosphere, at a temperature of from about 150° C. to 300° C. in the presence of a catalytic amount of a catalyst comprising about 0.45 to 0.71 grams of palladium in a palladium salt, about 0.30 to 1.2 grams of copper in a copper salt and about 0.30 to 1.1 grams of chloride ion, all per mole of alkanediol.
Claim 3
Dependent Claim
15 words
A process as recited in claim 1 in which the palladium salt is palladium chloride.
Claim 4
Dependent Claim
26 words
A process as recited in claim 2 in which the copper salt is selected from the group consisting of cupric chloride, cupric nitrate and mixtures thereof.
Claim 5
Dependent Claim
28 words
A process as recited in claim 1 in which the catalyst concentration in the reaction mixture is in the range from about 0.1 to 1% by weight thereof.
Claim 6
Dependent Claim
94 words
A process for the preparation of an unsubstituted cyclic ether which comprises reacting an unsubstituted alkanediol selected from the group consisting of 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol in the liquid phase, in a molecular oxygen gaseous atmosphere, at a temperature of from about 150° C. to 300° C. in the presence of a catalytic amount of a catalyst comprising about 0.45 to 0.71 grams of palladium in a palladium salt, about 0.30 to 1.2 grams of copper in a copper salt and about 0.30 to 1.1 grams of chloride ion, all per mole of alkanediol.
Claim 7
Dependent Claim
94 words
A process for the preparation of an unsubstituted cyclic ether which comprises reacting an unsubstituted alkanediol selected from the group consisting of 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol in the liquid phase, in a molecular oxygen gaseous atmosphere, at a temperature of from about 150° C. to 300° C. in the presence of a catalytic amount of a catalyst comprising about 0.45 to 0.71 grams of palladium in a palladium salt, about 0.30 to 1.2 grams of copper in a copper salt and about 0.30 to 1.1 grams of chloride ion, all per mole of alkanediol.
Claim 8
Dependent Claim
15 words
A process as recited in claim 5 in which the palladium salt is palladium chloride.
Claim 9
Dependent Claim
26 words
A process as recited in claim 6 in which the copper salt is selected from the group consisting of cupric chloride, cupric nitrate and mixtures thereof.
Claim 10
Dependent Claim
28 words
A process as recited in claim 5 in which the catalyst concentration in the reaction mixture is in the range from about 0.1 to 1% by weight thereof.
Claim 11
Dependent Claim
92 words
A process for the preparation of tetrahydrofuran which comprises reacting 1,4-butanediol in the liquid phase, in a molecular oxygen gaseous atmosphere, at a temperature of from about 150° C. to 300° C. in the presence of a catalytic amount of a catalyst comprising palladium chloride and a copper salt wherein palladium is present in an amount of about 0.45 to 0.71 grams, copper is present in an amount of about 0.30 to 1.2 grams and chloride is present in an amount of about 0.30 to 1.1 grams, all per mole of butanediol.
Claim 12
Dependent Claim
92 words
A process for the preparation of tetrahydrofuran which comprises reacting 1,4-butanediol in the liquid phase, in a molecular oxygen gaseous atmosphere, at a temperature of from about 150° C. to 300° C. in the presence of a catalytic amount of a catalyst comprising palladium chloride and a copper salt wherein palladium is present in an amount of about 0.45 to 0.71 grams, copper is present in an amount of about 0.30 to 1.2 grams and chloride is present in an amount of about 0.30 to 1.1 grams, all per mole of butanediol.
Claim 13
Dependent Claim
21 words
A process as recited in claim 9 in which the copper salt is cupric chloride, cupric nitrate or a mixture thereof.
Claim 14
Dependent Claim
92 words
A process for the preparation of tetrahydropyran which comprises reacting 1,5-pentanediol in the liquid phase, in a molecular oxygen gaseous atmosphere, at a temperature of from about 150° C. to 300° C. in the presence of a catalytic amount of a catalyst comprising palladium chloride and a copper salt wherein palladium is present in an amount of about 0.45 to 0.71 grams, copper is present in an amount of about 0.30 to 1.2 grams and chloride is present in an amount of about 0.30 to 1.1 grams, all per mole of butanediol.
Claim 15
Dependent Claim
92 words
A process for the preparation of tetrahydropyran which comprises reacting 1,5-pentanediol in the liquid phase, in a molecular oxygen gaseous atmosphere, at a temperature of from about 150° C. to 300° C. in the presence of a catalytic amount of a catalyst comprising palladium chloride and a copper salt wherein palladium is present in an amount of about 0.45 to 0.71 grams, copper is present in an amount of about 0.30 to 1.2 grams and chloride is present in an amount of about 0.30 to 1.1 grams, all per mole of butanediol.
Claim 16
Dependent Claim
21 words
A process as recited in claim 11 in which the copper salt is cupric chloride, cupric nitrate or a mixture thereof.
Claim 17
Dependent Claim
92 words
A process for the preparation of 2,5-dimethyltetrahydrofuran which comprises reacting 2,5-hexanediol in the liquid phase, in a molecular oxygen gaseous atmosphere, at a temperature of from about 150° C. to 300° C. in the presence of a catalytic amount of a catalyst comprising palladium chloride and a copper salt wherein palladium is present in an amount of about 0.45 to 0.71 grams, copper is present in an amount of about 0.30 to 1.2 grams and chloride is present in an amount of about 0.30 to 1.1 grams, all per mole of butanediol.
Claim 18
Dependent Claim
92 words
A process for the preparation of 2,5-dimethyltetrahydrofuran which comprises reacting 2,5-hexanediol in the liquid phase, in a molecular oxygen gaseous atmosphere, at a temperature of from about 150° C. to 300° C. in the presence of a catalytic amount of a catalyst comprising palladium chloride and a copper salt wherein palladium is present in an amount of about 0.45 to 0.71 grams, copper is present in an amount of about 0.30 to 1.2 grams and chloride is present in an amount of about 0.30 to 1.1 grams, all per mole of butanediol.
Claim 19
Dependent Claim
21 words
A process as recited in claim 13 in which the copper salt is cupric chloride, cupric nitrate or a mixture thereof.
Claim 20
Dependent Claim
92 words
A process for the preparation of 2,2,5,5-tetramethyldihydrofuran which comprises reacting 2,5-dimethylhexane-2,5-diol in the liquid phase, in a molecular oxygen gaseous atmosphere, at a temperature of from about 150° C. to 300° C. in the presence of a catalytic amount of a catalyst comprising palladium chloride and a copper salt wherein palladium is present in an amount of about 0.45 to 0.71 grams, copper is present in an amount of about 0.30 to 1.2 grams and chloride is present in an amount of about 0.30 to 1.1 grams, all per mole of butanediol.
Claim 21
Dependent Claim
92 words
A process for the preparation of 2,2,5,5-tetramethyldihydrofuran which comprises reacting 2,5-dimethylhexane-2,5-diol in the liquid phase, in a molecular oxygen gaseous atmosphere, at a temperature of from about 150° C. to 300° C. in the presence of a catalytic amount of a catalyst comprising palladium chloride and a copper salt wherein palladium is present in an amount of about 0.45 to 0.71 grams, copper is present in an amount of about 0.30 to 1.2 grams and chloride is present in an amount of about 0.30 to 1.1 grams, all per mole of butanediol.
Claim 22
Dependent Claim
21 words
A process as recited in claim 15 in which the copper salt is cupric chloride, cupric nitrate or a mixture thereof.
Claim 23
Dependent Claim
19 words
A process according to claim 1, wherein said chloride ion is the anion of said palladium or copper salt.
Claim 24
Dependent Claim
25 words
A process according to claim 1, wherein said chloride ion is supplied as the anion of a salt other than said palladium and copper salt.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-09-07 | 1985-03-09 | 1985-09-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-09-07 | 1989-03-09 | 1989-09-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-09-07 | 1993-03-09 | 1993-09-08 | $7700.00 | Window Closed / Lapsed |