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US4262122A
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Preparation of 5,5-dimethyl-2-hydrazino-1,4,5,6-tetrahydro-pyrimidine hydrohalide
Assignee: Wyeth Holdings LLC
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Filing: 1980-02-19
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Granted: 1981-04-14
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Expires: 2000-02-19
Abstract
Abstract There is provided a novel process for preparing 5,5-dimethyl-2-hydrazino-1,4,5,6-tetrahydropyrimidine hydrohalide by causing neopentyldiamine to react with a guanidine hydrohalide and followed by treating the so-formed reaction product with hydrazine to yield the desired tetrahydropyrimidine hydrohalide. Alternatively, neopentyldiamine, guanidine hydrohalide and hydrazine can be admixed and reacted to yield the desired tetrahydropyrimidine hydrohalide.
Inventors
- 👤 Robert G. Lees
- 👤 Andrew S. Tomcufcik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:54
CPC Classifications
C; C07; C07D; C07D239/00; C07D239/02; C07D239/06; C07D239/08; C07D239/12; C07D239/18; C07D239/14
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
44 words
A process for the preparation of 5,5-dimethyl-2-hydrazino-1,4,5,6-tetrahydropyrimidine hydrohalide which comprises: reacting in at least equimolar amounts neopentyldiamine, hydrazine hydrate and guanidine hydrohalide, at a temperature ranging from about 110° C. to about 160° C., and recovering resultant 5,5-dimethyl-2-hydrazino-1,4,5,6-tetrahydropyrimidine hydrohalide in good yield and purity.
Claim 2
Dependent Claim
44 words
A process for the preparation of 5,5-dimethyl-2-hydrazino-1,4,5,6-tetrahydropyrimidine hydrohalide which comprises: reacting in at least equimolar amounts neopentyldiamine, hydrazine hydrate and guanidine hydrohalide, at a temperature ranging from about 110° C. to about 160° C., and recovering resultant 5,5-dimethyl-2-hydrazino-1,4,5,6-tetrahydropyrimidine hydrohalide in good yield and purity.
Claim 3
Dependent Claim
13 words
The process according to claim 1 wherein the guanidine hydrohalide is guanidine hydrochloride.
Claim 4
Dependent Claim
30 words
The process according to claim 1 wherein a mixture of neopentyldiamine and guanidine hydrohalide is initially reacted to form 5,5-dimethyl-2-amino-1,4,5,6-tetrahydropyrimidine hydrohalide and further reacting the latter with the hydrazine reactant.
Claim 5
Dependent Claim
13 words
The process according to claim 3 wherein the guanidine hydrohalide is guanidine hydrochloride.
Claim 6
Dependent Claim
46 words
In a process for the preparation of 5,5-dimethyl-2-hydrazino-1,4,5,6-tetrahydropyrimidine hydrohalide, the improvement which comprises: reacting a 5,5-dimethyl-2-amino-1,4,5,6-tetrahydropyrimidine hydrohalide with at least an equivalent of hydrazine hydrate at a temperature ranging from about 120° C. to about 135° C. and recovering 5,5-dimethyl-2-hydrazino-1,4,5,6-tetrahydropyrimidine hydrohalide in good yield and purity.
Claim 7
Dependent Claim
46 words
In a process for the preparation of 5,5-dimethyl-2-hydrazino-1,4,5,6-tetrahydropyrimidine hydrohalide, the improvement which comprises: reacting a 5,5-dimethyl-2-amino-1,4,5,6-tetrahydropyrimidine hydrohalide with at least an equivalent of hydrazine hydrate at a temperature ranging from about 120° C. to about 135° C. and recovering 5,5-dimethyl-2-hydrazino-1,4,5,6-tetrahydropyrimidine hydrohalide in good yield and purity.
Claim 8
Dependent Claim
11 words
The process according to claim 5 wherein the hydrohalide is hydrochloride.
References Cited (Backward Citations)
US3931152A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-04-13 | 1984-10-13 | 1985-04-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-04-13 | 1988-10-13 | 1989-04-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-04-13 | 1992-10-13 | 1993-04-14 | $7700.00 | Window Closed / Lapsed |