US3676514A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for adding methyl substituents to aromatic hydrocarbons
Assignee: Gulf Research and Development Co
•
Filing: 1959-09-05
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Granted: 1972-07-11
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Expires: 1979-09-05
Abstract
Abstract A process for adding from one to two methyl substituents to an aromatic hydrocarbon which involves reacting the aromatic hydrocarbon with formaldehyde in an aqueous HCl medium in an atmosphere containing gaseous HCl at an elevated pressure to obtain a chloromethyl aromatic hydrocarbon, reacting the chloromethyl aromatic hydrocarbon with hydrogen in the presence of a hydrogenation catalyst and gaseous HCl at an elevated pressure to obtain the desired methyl aromatic hydrocarbon, hydrogen and gaseous HCl and recycling the latter hydrogen and gaseous HCl to the first stage of the process.
Inventors
- 👤 Robert W Rosenthal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:38
CPC Classifications
C; C07; C07C; C07C15/00; C07C15/02; C07C1/00; C07C1/26; C07C2521/00; C07C2521/18; C07C2523/00; C07C2523/38; C07C2523/40; C07C2523/44; Y; Y10; Y10S; Y10S585/00; Y10S585/929; Y10S585/93; Y10S585/935
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
11 words
The process of claim 1 wherein the reactant aromatic is pseudocumene.
Claim 2
Dependent Claim
19 words
The process of claim 1 wherein the reactant aromatic is pseudocumene and the hydrogenation catalyst is palladium on carbon.
Claim 3
Dependent Claim
22 words
The process of claim 1 wherein the reactant aromatic is pseudocumene and the operation consumes substantially solely aromatic hydrocarbon, formaldehyde and hydrogen.
Claim 4
Dependent Claim
11 words
The process of claim 1 wherein the polar solvent is ethanol.
Claim 5
Dependent Claim
25 words
The process of claim 1 wherein the reactant aromatic is pseudocumene and the temperature in the second stage is about 25* to about 80* C.
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) | 1975-07-11 | 1976-01-10 | 1976-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-11 | 1980-01-10 | 1980-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-11 | 1984-01-10 | 1984-07-11 | $7700.00 | Window Closed / Lapsed |