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US3948966A
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Process for preparing benzene derivatives having isocyanatomethyl group
Assignee: DEN-TAL-EZ DENTAL PRODUCTS CORP A CORP OF PA
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Filing: 1974-10-11
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Granted: 1976-04-06
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Expires: 1994-10-11
Abstract
Abstract A process for preparing benzene derivatives having an isocyanatomethyl group by reacting a benzene derivative having a chloromethyl group with sodium cyanate in dimethylformamide at 60° to 160°C., in the presence of a catalytic amount of an acidic metal chloride-dimethylformamide compound, made present in the reaction mixture from the start of the reaction by being dissolved in the starting reaction mixture.
Inventors
- 👤 Yoshiaki Inamoto
- 👤 Hisao Kitano
- 👤 Yoshiaki Tanaka
- 👤 Fumio Tanimoto
- 👤 Atsushi Nishibata
- 👤 Susumu Handa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 07:07
CPC Classifications
C; C07; C07C; C07C263/00; C07C263/02
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
118 words
A process for preparing benzene derivatives having one or more isocyanatomethyl side chains, comprising the steps of: adding to liquid dimethylformamide having completely dissolved therein a catalytic amount of acidic metal chloride-dimethylformamide compound in which said acidic metal chloride moiety is selected from the group consisting of lithium chloride, copper chloride, beryllium chloride, magnesium chloride, calcium chloride, zinc chloride, aluminum chloride, silicon chloride, titanium chloride, zirconium chloride, vanadium chloride, chromium chloride, iron chloride, their corresponding oxychlorides and mixtures thereof, reactants consisting essentially of 1. a benzene derivative selected from the group consisting of chloromethylbenzene, bis-chloromethylbenzene, tris-chloromethylbenzene and nucleus-substituted derivatives thereof wherein the substituents are free of atoms of elements other than hydrogen, carbon, chlorine and oxygen, and 2.
Claim 2
Dependent Claim
118 words
A process for preparing benzene derivatives having one or more isocyanatomethyl side chains, comprising the steps of: adding to liquid dimethylformamide having completely dissolved therein a catalytic amount of acidic metal chloride-dimethylformamide compound in which said acidic metal chloride moiety is selected from the group consisting of lithium chloride, copper chloride, beryllium chloride, magnesium chloride, calcium chloride, zinc chloride, aluminum chloride, silicon chloride, titanium chloride, zirconium chloride, vanadium chloride, chromium chloride, iron chloride, their corresponding oxychlorides and mixtures thereof, reactants consisting essentially of 1. a benzene derivative selected from the group consisting of chloromethylbenzene, bis-chloromethylbenzene, tris-chloromethylbenzene and nucleus-substituted derivatives thereof wherein the substituents are free of atoms of elements other than hydrogen, carbon, chlorine and oxygen, and 2.
Claim 3
Dependent Claim
42 words
sodium cyanate having a purity of at least 70 weight percent, and reacting the resulting mixture at a temperature of 60° to 160°C. until there is formed the corresponding benzene derivative having one or more isocyanatomethyl side chains, and recovering the latter
Claim 4
Dependent Claim
42 words
sodium cyanate having a purity of at least 70 weight percent, and reacting the resulting mixture at a temperature of 60° to 160°C. until there is formed the corresponding benzene derivative having one or more isocyanatomethyl side chains, and recovering the latter
Claim 5
Dependent Claim
35 words
benzene derivative from the reaction mixture. 2. A process according to claim 1, in which the dimethylformamide contains from 0 to 15 weight percent of organic solvents and 0 to 5 weight percent of water.
Claim 6
Dependent Claim
23 words
A process according to claim 1, in which said acidic metal chloride-dimethylformamide compound is prepared by reacting anhydrous acidic metal chloride with dimethylformamide.
Claim 7
Dependent Claim
25 words
A process according to claim 3, in which said acidic metal chloride forms a solution having a pH lower than 7 when dissolved in water.
Claim 8
Dependent Claim
38 words
A process according to claim 3, in which the amount of said acidic metal chloride-dimethylformamide compound is from 0.01 to 10 mole percent, based on the amount of sodium cyanate, both calculated on the 100 % purity basis.
Claim 9
Dependent Claim
35 words
A process according to claim 1, in which the amount of reactant (2) is from 0.9 to 1.6 moles, per mole of chloromethyl groups of reactant (1), both calculated on a 100 % purity basis.
Claim 10
Dependent Claim
24 words
A process according to claim 7, in which the amount of liquid dimethylformamide is from 1 to 10 moles, per mole of reactant (1).
Claim 11
Dependent Claim
28 words
A process according to claim 1 in which said acidic metal chloride is selected from the group consisting of lithium chloride, magnesium chloride, calcium chloride and zinc chloride.
References Cited (Backward Citations)
US2866801A
Cited
US3584028A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-04-06 | 1979-10-06 | 1980-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-06 | 1983-10-06 | 1984-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-06 | 1987-10-06 | 1988-04-06 | $7700.00 | Window Closed / Lapsed |