Difference between revisions of "Methylamine"
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==Availability== | ==Availability== | ||
| − | Methylamine is sold by various chemical suppliers. | + | Methylamine is sold by various chemical suppliers, either as compressed gas or salt. |
===Legality=== | ===Legality=== | ||
Revision as of 15:44, 29 September 2017
| Names | |
|---|---|
| IUPAC name
Methanamine
| |
| Other names
Aminomethane
Carbinamine Glycamine Mercurialin Monomethylamine MeNH2 MMA | |
| Properties | |
| CH5N CH3NH2 | |
| Molar mass | 31.06 g/mol |
| Appearance | Colorless gas |
| Odor | Fishy, ammoniacal |
| Density | 1.4 g/l (gas) 0.6624 g/cm3 (liquid, at 25 °C) |
| Melting point | −93.10 °C (−135.58 °F; 180.05 K) |
| Boiling point | −6.6 °C (20.1 °F; 266.5 K) |
| 1.008 g/L (at 20 °C) | |
| Solubility | Miscible in diethyl ether Soluble in acetone, benzene, ethanol, methanol, THF |
| Thermochemistry | |
| Std enthalpy of
formation (ΔfH |
−23.5 kJ mol−1 |
| Hazards | |
| Safety data sheet | Sigma-Aldrich |
| Flash point | −10 °C |
| Lethal dose or concentration (LD, LC): | |
| LD50 (Median dose)
|
100 mg kg−1 (oral, rat) |
| LC50 (Median concentration)
|
1,860 ppm (mouse, 2 hr) |
| Related compounds | |
| Related compounds
|
Ammonia Dimethylamine Trimethylamine |
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
| Infobox references | |
Methylamine or methanamine is a colorless gas with a strong fishy odor, having the formula CH3NH2 (sometimes shortened to MeNH2). It is an organic compound, the simplest primary amine.
Contents
Properties
Chemical
Methylamine reacts with acids to form methylammonium salts, such as methylammmonium chloride (or methylamine hydrochloride):
- CH3NH2 + HCl → CH3NH3Cl
Physical
Methylamine is a colorless gas, heavier than air with a strong fish-like odor. It is very soluble in water and various organic solvents.
Availability
Methylamine is sold by various chemical suppliers, either as compressed gas or salt.
Legality
In US, methylamine and its salts are DEA List I chemicals, due to their use in the production of methamphetamine, and as such cannot be purchased freely.
Many other countries have similar restrictions.
Preparation
There are several routes to methylamine.
The industrial process involves the reaction of methanol with anhydrous ammonia, in the presence of a drying catalyst, such as silica gel or more effective, a zeolite based catalyst. The reaction takes place at high temperatures, and dimethylamine and trimethylamine are also produced as side products with the latter being the most favoured by the reaction kinetics. Methylamine can be extracted from the mixture via either fractional distillation or other convenient methods.[1]
The most convenient route is by refluxing a mixture of formaldehyde and ammonium chloride, at around 104 °C.
- NH4Cl + 2 H2CO → CH3NH2·HCl + HCOOH
Both reagents are readily available in most places and the final product of the reaction is methylammonium chloride, which is solid and non-volatile, which makes the reaction safe. However, extracting the methylamine hydrochloride from the product proves frustrating, though it's perfectly possible.[2]
To obtain freebase methylamine, MeNH2·HCl is reacted with a base, such as sodium hydroxide.
Hofmann rearrangement of acetamide (made from the dehydration of ammonium acetate) will give methylamine.
Hydrolysis of methyl isocyanate will also yield methylamine. However, the precursor is very toxic, which makes the reaction dangerous and impractical.
Another route involves the reduction of nitromethane with Zn/HCl.
Projects
- Make methylamommium halides
- Make methylammonium nitrate
- Make methylammonium perchlorate
- Make Metol
Handling
Safety
Methylamine is toxic and proper protection should be worn when handling the product.
Storage
Methylamine is best stored as a salt.
Anhydrous methylamine can be stored in compressed cylinders.
Disposal
Methylamine salts pose little danger to environment and (generally) don't require special disposal.
References
- ↑ http://www.sciencedirect.com/science/article/pii/S0920586197000035
- ↑ http://www.youtube.com/watch?v=xIWfnQr7168
