US3110730A - Process for preparing methylhydrazine - Google Patents

Process for preparing methylhydrazine Download PDF

Info

Publication number
US3110730A
US3110730A US35392A US3539260A US3110730A US 3110730 A US3110730 A US 3110730A US 35392 A US35392 A US 35392A US 3539260 A US3539260 A US 3539260A US 3110730 A US3110730 A US 3110730A
Authority
US
United States
Prior art keywords
methylhydrazine
distillate
preparing
temperature
hydrazinoalcohol
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US35392A
Inventor
Gever Gabriel
John C Howard
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US35392A priority Critical patent/US3110730A/en
Application granted granted Critical
Publication of US3110730A publication Critical patent/US3110730A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/51—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by pyrolysis, rearrangement or decomposition
    • C07C45/511—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by pyrolysis, rearrangement or decomposition involving transformation of singly bound oxygen functional groups to >C = O groups
    • C07C45/512—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by pyrolysis, rearrangement or decomposition involving transformation of singly bound oxygen functional groups to >C = O groups the singly bound functional group being a free hydroxyl group
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C241/00—Preparation of compounds containing chains of nitrogen atoms singly-bound to each other, e.g. hydrazines, triazanes
    • C07C241/02—Preparation of hydrazines

Definitions

  • This invention relates to a novel process for preparing methylhydrazine. More particularly, the present invention relates to a process for the preparation of methylhydrazine from 2-hydrazinoalcohols.
  • Methylhydrazine is useful as an intermediate in the preparation of pharmacologically active substances; e.g., S-nitrO-Z-furaldehyde 2-methyl semicarbazone; in the preparation of herbicides; and as a reducing agent.
  • a Z-hydrazinoalcohol is placed in a suitable reaction vessel and heat supplied to cause decomposition.
  • the desired end product of the decomposition, methylhydrazine, is collected by distillation.
  • a schema representative of the course of our invention is as follows:
  • a Z-hydrazinoalcohol for instance, Z-hydroxyethylhydrazine or Z-hydroxypropylhydrazine
  • a suitable reaction vessel which is adapted for distillation. Heat is supplied externally for about 1 to 6 hours.
  • a temperature of from about ZOO-225 C. causes decomposition of the Z-hydrazinoalcohol.
  • the liquid decomposition products are collected as the distillate.
  • This distillate is further fractionated, preferably at reduced pressure, to obtain an azeotropic mixture of methylhydrazine and water which is dried with a suitable drying agent such as sodium hydroxide and further distilled at atmospheric pressure to obtain methylhydrazine.
  • the method which we now prefer consists in placing 2- hydroxyethylhydrazine in a suitable reaction vessel, adding polyethylene glycol 400 as an inert heat absorbing medium and heating the vessel at a temperature of from 215220 C. for about one hour.
  • the collected distillate containing methylhydrazine is distilled in vacuo and the fraction distilling at room temperature at 14 mm. of mercury pressure is collected.
  • This fraction consisting essentially of water and methylhydrazine is redistilled at atmospheric pressure and the distillate therefrom is dried over sodium hydroxide while heating at a temperature of from 75-90" C. It is then fractionated through a suitable column,
  • Fraction I is redistilled at atmospheric pressure yielding 35.1 g. of a liquid having a boiling range of 81-104 C. and consisting essentially of methylhydrazine and its water azeotrope. This liquid is dried over sodium hydroxide at steam bath temperature and then distilled at atmospheric pressure through a Vigreux column giving 13.9 g. of methylhydrazine, boiling point 8687 C.
  • a process for preparing methylhydrazine by thermal decomposition of a Z-hydrazinoalcohol selected from the group consisting of 2-hydroxyethylhydrazine and 2-hydroxypropylhydrazine which comprises subjecting said hydrazinoalcohol to exothermic thermal decomposition at a temperature of from about 200 to 225 C., collecting the liquid distillate and recovering methylhydrazine therefrom by redistillation.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Description

United States Patent 3,110,730 PROCESS FOR PREPARING METHYLI-IYDRAZINE Gabriel Gever, Scott St, flxford, N.Y., and John C. Howard, 13 Brown Ave, Norwich, N .Y. No Drawing. Filed June 13, 1960, Ser. No. 35,392 1 Claim. (Cl. 260 -533) This invention relates to a novel process for preparing methylhydrazine. More particularly, the present invention relates to a process for the preparation of methylhydrazine from 2-hydrazinoalcohols.
Methylhydrazine is useful as an intermediate in the preparation of pharmacologically active substances; e.g., S-nitrO-Z-furaldehyde 2-methyl semicarbazone; in the preparation of herbicides; and as a reducing agent.
We have made the surprising discovery that it is possible to prepare methylhydrazine very readily by the thermal decomposition of Z-hydrazino-alcohols. The pyrolysis proceeds straightforwardly in ordinarily available processing equipment. The starting materials are readily procurable at modest cost.
In accordance with our invention a Z-hydrazinoalcohol is placed in a suitable reaction vessel and heat supplied to cause decomposition. The desired end product of the decomposition, methylhydrazine, is collected by distillation. A schema representative of the course of our invention is as follows:
In the practice of our invention a Z-hydrazinoalcohol, for instance, Z-hydroxyethylhydrazine or Z-hydroxypropylhydrazine, is placed in a suitable reaction vessel which is adapted for distillation. Heat is supplied externally for about 1 to 6 hours. A temperature of from about ZOO-225 C. causes decomposition of the Z-hydrazinoalcohol. The liquid decomposition products are collected as the distillate. This distillate is further fractionated, preferably at reduced pressure, to obtain an azeotropic mixture of methylhydrazine and water which is dried with a suitable drying agent such as sodium hydroxide and further distilled at atmospheric pressure to obtain methylhydrazine.
In the practice of our invention we have found the addition of an inert high boiling diluent such as polyethylene glycol 400 to the reaction vessel containing the 2-hydrazinoalcohol prior to pyrolysis to be advantageous in mitigating too violent decomposition which sometimes occurs.
The method which we now prefer consists in placing 2- hydroxyethylhydrazine in a suitable reaction vessel, adding polyethylene glycol 400 as an inert heat absorbing medium and heating the vessel at a temperature of from 215220 C. for about one hour. The collected distillate containing methylhydrazine is distilled in vacuo and the fraction distilling at room temperature at 14 mm. of mercury pressure is collected. This fraction consisting essentially of water and methylhydrazine is redistilled at atmospheric pressure and the distillate therefrom is dried over sodium hydroxide while heating at a temperature of from 75-90" C. It is then fractionated through a suitable column,
such as a Vigreux, and the desired product, methylhydrazine, obtained.
3,1 10,730 Patented Nov. 12, I963 "ice In order that our invention may be readily available to and understood by those skilled in the art the following examples are illustrative:
EXAMPLE I Thermal Decomposition of 2-Hydroxyethylhydrazine In a 200 ml. flask set up for distillation and having a gas outlet tube connected to a trap containing dilute hydrochloric acid is placed 116 g. (1.53 moles) of Z-hydroxyethylhydrazine. The flask is heated in an oil bath to a temperature of 2l5220 C. for about one hour. A total of 75.5 g. of distillate is collected in this time.- This distillate is distilled in vacuo. A fraction (I) 39.2 g. distilling at room temperature at 14 mm. of mercury, and a smaller fraction (II), 2.3 g. having a boiling point of 50 C. at 3.0 mm. of mercury are obtained. Fraction I is redistilled at atmospheric pressure yielding 35.1 g. of a liquid having a boiling range of 81-104 C. and consisting essentially of methylhydrazine and its water azeotrope. This liquid is dried over sodium hydroxide at steam bath temperature and then distilled at atmospheric pressure through a Vigreux column giving 13.9 g. of methylhydrazine, boiling point 8687 C.
EXAMPLE II Thermal Decomposition of 2-Hydroxypropylhydrazine In a 500 ml. fiask equipped with a stirrer, thermometer, a gas outlet tube leading to an acid trap and a variable take-off assembly is placed 301 g. (3.34 moles) of 2-hydroxypropylhydrazine. The flask is heated to 210 C. with a mantle. After 5 /2 hours 187 g. of distillate having a boiling range of 125-145 C. are collected. During the distillation a reflux rate of 3:1 is used. The bulk of the distillate, 164 g, is distilled through a Vigreux column. The distillate having a boiling range of 95108 and amounting to 112 g. is dried over sodium hydroxide at room temperature for eight hours. The organic layer is decanted and further dried over sodium hydroxide at refrigerator temperature for 12 hours. The organic layer is filtered through glass wool and then distilled through a Vigreux column. Two fractions are obtained: I having a boiling point of -86 C. and amounting to 9.5 g. is methylhydrazine; and II having a boiling range of 929 7 C. and amounting to 31 g. which is a methylhydrazine derivative readily converted to methylhydrazine by treatment with dilute acid.
What is claimed is:
A process for preparing methylhydrazine by thermal decomposition of a Z-hydrazinoalcohol selected from the group consisting of 2-hydroxyethylhydrazine and 2-hydroxypropylhydrazine, which comprises subjecting said hydrazinoalcohol to exothermic thermal decomposition at a temperature of from about 200 to 225 C., collecting the liquid distillate and recovering methylhydrazine therefrom by redistillation.
References Cited in the file of this patent Gabriel: Ber., Vol.47, pp. 302833 (1914), C.A. 9321.
US35392A 1960-06-13 1960-06-13 Process for preparing methylhydrazine Expired - Lifetime US3110730A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US35392A US3110730A (en) 1960-06-13 1960-06-13 Process for preparing methylhydrazine

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US35392A US3110730A (en) 1960-06-13 1960-06-13 Process for preparing methylhydrazine

Publications (1)

Publication Number Publication Date
US3110730A true US3110730A (en) 1963-11-12

Family

ID=21882394

Family Applications (1)

Application Number Title Priority Date Filing Date
US35392A Expired - Lifetime US3110730A (en) 1960-06-13 1960-06-13 Process for preparing methylhydrazine

Country Status (1)

Country Link
US (1) US3110730A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3272839A (en) * 1961-09-29 1966-09-13 Hoffmann La Roche Substituted methylhydrazine compounds

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3272839A (en) * 1961-09-29 1966-09-13 Hoffmann La Roche Substituted methylhydrazine compounds

Similar Documents

Publication Publication Date Title
Eliel et al. Conformational analysis. XVII. 2-Alkoxy-and 2-alkylthiotetrahydropyrans and 2-alkoxy-1, 3-dioxanes. Anomeric effect
JPH06234667A (en) Preparation of aromatic bromomethyl compound
US3110730A (en) Process for preparing methylhydrazine
US4948780A (en) Alcohols and ethers having cyclododecyl and cyclododecenyl groups, process for their preparation and scents containing same
US3836568A (en) Process for production of lower alkyl esters of cis-chrysanthemum monocarboxylic acid
US2407508A (en) Unsaturated bicyclic carbonylic compounds and their preparation
Smith et al. The Action of Aliphatic Diazo Compounds upon α, β-Unsaturated Ketones. III. 1 Benzalacetone and Diazomethane
DE2844635C2 (en) 2-propyl-pent-4-en-l-al and process for its preparation
Condon Synthesis of 1-alkyl-2-methylhydrazines by way of hydrazones of 1-acetyl-1-methylhydrazine
US2901506A (en) Pyrolysis of substituted carbonyloxyalkyl halides
US2454936A (en) Process for preparing unsaturated alcohols
US2681939A (en) Production of chlokomethwl methyl
DE1801663A1 (en) New fragrances and processes for their production
US2483201A (en) Process for the selective hydrogenation of arylnitroolefins and products thereof
HOWARD et al. The thermal decomposition of 2-hydrazinoethanol and 1-hydrazino-2-propanol
Skramstad Cyclopenta-thiophenes
DE818048C (en) Process for the preparation of 1, 2, 3-triazole derivatives
Dolbier Jr et al. A kinetic study of the thermal rearrangement of 2-(trifluoromethyl)-1-vinylcyclopropane
US2532279A (en) Hydrogenated furfuralacetofuran
US3248431A (en) Butyl nitrophenols
EP0612316A1 (en) Process for preparing 3(5)-methylpyrazoles.
US3781308A (en) Preparation of 5-benzyl-3-furylmethanol
US2516293A (en) Process for producing o-alkylimino ethers
Sands Preparation of Bicyclo [4.3. 1] dec-7-en-10-one
Willard et al. Studies in the Furan Series. Chloralfuramides and Some of their Reactions