Patent US3905973A successfully refreshed from Google Patents.
US3905973A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thiol methylation with methyl chloride
Assignee: EIDP Inc
•
Filing: 1974-06-18
•
Granted: 1975-09-16
•
Expires: 1994-06-18
Abstract
Abstract Compound A is methylated to produce compound B, in presence of a base in aqueous medium, using methyl chloride as alkylating agent and conducting the methylation in presence of sodium or potassium iodide.
Inventors
- 👤 Richard John Gobeil
- 👤 Frank Runar Haglid
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 03:24
CPC Classifications
C; C07; C07D; C07D253/00; C07D253/02; C07D253/06; C07D253/065; C07D253/07; C07D253/075
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
7 words
IN THE PROCESS OF SYNTHESIZING THE COMPOUND
Claim 2
Dependent Claim
7 words
IN THE PROCESS OF SYNTHESIZING THE COMPOUND
Claim 3
Dependent Claim
5 words
in presence of sodium hydroxide;
Claim 4
Dependent Claim
5 words
in presence of sodium hydroxide;
Claim 5
Dependent Claim
46 words
Improved process of claim 1 wherein a. the mole ratio of methyl chloride to compound A is in the range of 1-1.5; b. the mole ratio of sodium or potassium iodide to methyl chloride is in the range of about 0.02-1; c. the methylation is conducted
Claim 6
Dependent Claim
15 words
in presence of a base selected from the hydroxides and carbonates of sodium and potassium;
Claim 7
Dependent Claim
15 words
in presence of a base selected from the hydroxides and carbonates of sodium and potassium;
Claim 8
Dependent Claim
18 words
at pH in the range 7-14, temperature in the range of 20*-50*C., and at atmospheric or autogenous pressure.
Claim 9
Dependent Claim
18 words
at pH in the range 7-14, temperature in the range of 20*-50*C., and at atmospheric or autogenous pressure.
Claim 10
Dependent Claim
63 words
Improved process of claim 1 wherein a. the mole ratio of methyl chloride to compound A is in the range of about 1.05 to 1.2 and the methyl chloride is added to the reaction mixture gradually; b. the mole ratio of sodium or potasssium iodide to methyl chloride is in the range of about 0.1 to 0.5; and c. the methylation is conducted
Claim 11
Dependent Claim
18 words
pH in the range of about 10-12, temperature in the range of about 30*-40*C., and at autogenous pressure.
Claim 12
Dependent Claim
18 words
pH in the range of about 10-12, temperature in the range of about 30*-40*C., and at autogenous pressure.
Claim 13
Dependent Claim
12 words
Improved process of claim 3 wherein the methylation is conducted in water.
References Cited (Backward Citations)
US3135737A
Cited
US3671523A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-15 | 1979-03-17 | 1979-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-15 | 1983-03-17 | 1983-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-15 | 1987-03-17 | 1987-09-16 | $7700.00 | Window Closed / Lapsed |