Метандиамин гидрохлорид (1:2)

What is this substance

Methanediamine hydrochloride (1:2), also known as methylenediamine dihydrochloride (CAS 57166-92-4), is a salt of the simplest geminal diamine with two equivalents of hydrogen chloride. Composition CH6N2·2HCl. Synonyms: methanediamine dihydrochloride, diaminomethane dihydrochloride, methylenediamine bihydrochloride.

Purpose

Organic synthesis reagent, source of methylenediamine fragment H2N–CH2–NH2. The free base is unstable in its pure form, so the substance is supplied and stored as a dihydrochloride - the salt form is stable, soluble in water and easy to dose. The scope of application is laboratory and pilot-industrial synthesis; work with the reagent is carried out according to the methodology of a specific reaction.

Basic attributes (vendor card)

• Molecular weight: 118.99; exact weight: 118.00600
• EU number: 260-602-6
• UNII: WZB0836N6G
• BRN number: 3664689
• DSSTox ID: DTXSID4025531
• PSA: 52
• XLogP3: 1.86590

Physico-chemical indicators

• Density: 0.879 g/cm³
• Melting point: above 300°C
• Boiling point: 82.6 °C at 760 mm Hg. Art. — the value of the card contradicts the melting point and was transferred without editing
• Water solubility: 100 mg/ml or greater at 70.7°F (about 21.5°C)
• Reactions with air and water: soluble in water
• Fire Hazard: No flash point available, likely flammable (NTP, 1992)

Reactivity

Reactive group - acid salts. It is an acidic organic salt of an amine: in aqueous solution it behaves like an acid; solutions contain a moderate concentration of hydrogen ions and have a pH below 7.0. Neutralization of bases occurs with the release of heat, but noticeably less than during the neutralization of inorganic acids, inorganic oxoacids and carboxylic acids. Compounds of this group usually do not exhibit oxidative and reductive properties, although such behavior is not completely excluded. Many salts of this type catalyze organic reactions.

Safety Information

• GHS classification: Warning. H315 (100%) - causes skin irritation
• Precautions: P261, P264, P271, P280, P302+P352, P304+P340, P305+P351+P338, P312, P321, P332+P313, P337+P313, P362, P403+P233, P405, P501
• Reason: aggregated GHS data from 4 companies for 1 notification to the C&L ECHA register
• Transport codes: NONH - not classified as dangerous goods for any type of transport
• WGK Germany: 3
• Hazard class code: 36/37/38
• Safety instructions: 26-36
• Fire extinguishing: dry chemical powders, carbon dioxide or halon extinguishers (NTP, 1992)

Storage, spillage, protective equipment

Storage at 2–8 °C, container tightly closed; the 1992 NTP certificate directly refers to the refrigeration mode. The room is dry, the proximity to alkalis and strong oxidizing agents is excluded.

In case of a small spill, the solid material is moistened with water, transferred to a suitable container, and the residue is collected with damp absorbent paper. Contaminated clothing and paper are placed in a vapor-permeable plastic bag for disposal. Surfaces are washed with soapy water. Personnel may return to the premises after clearance has been confirmed by the responsible employee.

Minimum protection set according to NTP: disposable protective clothing of the Tyvek type or disposable Tyvek sleeves taped to gloves; when hanging and diluting a pure reagent - a half mask with NIOSH certification and a cartridge for organic vapors and acid gases with a dust and fog filter; splash goggles. A full facepiece respirator with the same cartridge provides eye and respiratory protection at the same time.