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US5338823A
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Lithium/HMPA-promoted synthesis of poly(phenylenes)
Assignee: Individual
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Filing: 1992-12-07
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Granted: 1994-08-16
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Expires: 2012-12-07
Abstract
Abstract Poly(phenylene) that is substantially free of insoluble material is prepared by the polymerization of a lithioarylhalide compound in the presence of a polar aprotic compound such as hexamethylphosphoramide, N,N,N',N'-tetramethylethylenediamine or hexamethylphosphorous triamide. The preferred reaction involves the polymerization of 1-bromo-4-lithiobenzene in the presence of hexamethylphosphoramide. The 1-bromo-4-lithiobenzene may be synthesized by reacting 1,4-dibromobenzene with t-butyllithium. These same types of reactions can also be used to synthesis other benzenoid polymers.
Inventors
- 👤 James M. Tour
- 👤 Eric B. Stephens
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 07:38
CPC Classifications
C; C08; C08G; C08G61/00; C08G61/02; C08G61/10; C08G2261/00; C08G2261/30; C08G2261/31; C08G2261/312
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
87 words
A method of preparing a benzenoid polymer comprising the steps of: (a) polymerizing a lithioarylhalide compound in the presence of a polar aprotic compound which is not decomposed by alkyllithium compounds; (b) separating the polymerized benzenoid polymer from any unreacted starting materials; (c) dissolving the separated material in a solvent; (d) treating the dissolved material with an excess of an alkyllithium compound that undergoes lithium/halogen exchange to replace halogen atoms attached to the polymer with lithium; and (e) quenching the lithiated polymer with an electrophile or water.
Claim 2
Independent Claim
87 words
A method of preparing a benzenoid polymer comprising the steps of: (a) polymerizing a lithioarylhalide compound in the presence of a polar aprotic compound which is not decomposed by alkyllithium compounds; (b) separating the polymerized benzenoid polymer from any unreacted starting materials; (c) dissolving the separated material in a solvent; (d) treating the dissolved material with an excess of an alkyllithium compound that undergoes lithium/halogen exchange to replace halogen atoms attached to the polymer with lithium; and (e) quenching the lithiated polymer with an electrophile or water.
Claim 3
Independent Claim
105 words
A method of preparing a benzenoid polymer comprising the steps of: (a) polymerizing a lithioarylhalide compound in the presence of a polar aprotic compound which is not decomposed by alkyllithium compounds wherein the polar aprotic compound is selected from the group consisting of hexamethyl phosphoramide, N,N,N',N'-tetramethylethylenediamine and hexamethylphosphorous triamide, (b) separating the polymerized benzenoid polymer from any unreacted starting materials; (c) dissolving the separated material in a solvent; (d) treating the dissolved material with an excess of an alkyllithium compound that undergoes lithium/halogen exchange to replace halogen atoms attached to the polymer with lithium; and (e) quenching the lithiated polymer with an electrophile or water.
Claim 4
Independent Claim
105 words
A method of preparing a benzenoid polymer comprising the steps of: (a) polymerizing a lithioarylhalide compound in the presence of a polar aprotic compound which is not decomposed by alkyllithium compounds wherein the polar aprotic compound is selected from the group consisting of hexamethyl phosphoramide, N,N,N',N'-tetramethylethylenediamine and hexamethylphosphorous triamide, (b) separating the polymerized benzenoid polymer from any unreacted starting materials; (c) dissolving the separated material in a solvent; (d) treating the dissolved material with an excess of an alkyllithium compound that undergoes lithium/halogen exchange to replace halogen atoms attached to the polymer with lithium; and (e) quenching the lithiated polymer with an electrophile or water.
Claim 5
Independent Claim
109 words
A method of preparing a benzenoid polymer comprising the steps of: (a) preparing a paralithioarylhalide by reacting a para-substituted aryldihalide with at least one equivalent of an alkyllithium compound that undergoes lithium/halogen exchange; (b) polymerizing the paralithioarylhalide compound in the presence of a polar aprotic compound which is not decomposed by alkyllithium compounds; (c) separating the polymerized benzenoid polymer from any unreacted starting materials; (d) dissolving the separated material in a solvent; (e) treating the dissolved material with an excess of an alkyllithium compound that undergoes lithium/halogen exchange to replace halogen atoms attached to the polymer with lithium; and (f) quenching the lithiated polymer with an electrophile or water.
Claim 6
Independent Claim
109 words
A method of preparing a benzenoid polymer comprising the steps of: (a) preparing a paralithioarylhalide by reacting a para-substituted aryldihalide with at least one equivalent of an alkyllithium compound that undergoes lithium/halogen exchange; (b) polymerizing the paralithioarylhalide compound in the presence of a polar aprotic compound which is not decomposed by alkyllithium compounds; (c) separating the polymerized benzenoid polymer from any unreacted starting materials; (d) dissolving the separated material in a solvent; (e) treating the dissolved material with an excess of an alkyllithium compound that undergoes lithium/halogen exchange to replace halogen atoms attached to the polymer with lithium; and (f) quenching the lithiated polymer with an electrophile or water.
Claim 7
Dependent Claim
55 words
A method according to claim 1, wherein the lithiated polymer is quenched with an electrophile selected from the group consisting of CO 2 , I 2 , Br 2 , Cl 2 , RCOH and RCOR', wherein R and R', which may be the same or different, are alkyl, alkenyl, alkynyl, aryl, alkoxy or amide.
Claim 8
Dependent Claim
55 words
A method according to claim 3, wherein the lithiated polymer is quenched with an electrophile selected from the group consisting of CO 2 , I 2 , Br 2 , Cl 2 , RCOH and RCOR', wherein R and R', which may be the same or different, are alkyl, alkenyl, alkynyl, aryl, alkoxy or amide.
Claim 9
Dependent Claim
20 words
A method according to claim 1, wherein the lithiated polymer is quenched with water whereby a halogen-free polymer is formed.
Claim 10
Dependent Claim
20 words
A method according to claim 3, wherein the lithiated polymer is quenched with water whereby a halogen-free polymer is formed.
Claim 11
Independent Claim
56 words
A method for dehalogenation of soluble poly(phenylene) comprising the steps of (a) dissolving the poly(phenylene) in a solvent; (b) reacting the dissolved material with an excess of an alkyllithium that undergoes lithium/halogen exchange to replace halogen atoms attached to the poly(phenylene) with lithium; and (c) quenching the lithiated poly(phenylene) with water to form a halogen-free poly(phenylene).
Claim 12
Independent Claim
56 words
A method for dehalogenation of soluble poly(phenylene) comprising the steps of (a) dissolving the poly(phenylene) in a solvent; (b) reacting the dissolved material with an excess of an alkyllithium that undergoes lithium/halogen exchange to replace halogen atoms attached to the poly(phenylene) with lithium; and (c) quenching the lithiated poly(phenylene) with water to form a halogen-free poly(phenylene).
References Cited (Backward Citations)
US4576688A
Cited
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1997-08-15 | 1998-02-14 | 1998-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-08-15 | 2002-02-14 | 2002-08-16 | $3760.00 | Window Closed / Lapsed |
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