Chloroform 99.9% 1Lt
Chloroform, or trichloromethane, is an organic compound with formula CHCl3. It is a colorless, sweet-smelling, dense liquid that is produced on a large scale as a precursor to PTFE. It is also a precursor to various refrigerants. It is one of the four chloromethanes and a trihalomethane. It is a powerful anesthetic, euphoriant, anxiolytic and sedative when inhaled or ingested.
Properties
Chemical formula: CHCl3
Molecular weight: 119.37 g·mol−1
Boiling point: 61.15 °C
Melting point: −63.5 °C
Density: 1.489 g/cm3 (25 °C)
Solubility in water: 10.62 g/L (0 °C)
8.09 g/L (20 °C)
7.32 g/L (60 °C)
Chemical structure
Safety
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Description
In terms of scale, the most important reaction of chloroform is with hydrogen fluoride to give monochlorodifluoromethane (CFC-22), a precursor in the production of polytetrafluoroethylene (Teflon):
- CHCl3 + 2 HF → CHClF2 + 2 HCl
The reaction is conducted in the presence of a catalytic amount of mixed antimony halides. Chlorodifluoromethane is then converted into tetrafluoroethylene, the main precursor to Teflon. Before the Montreal Protocol, chlorodifluoromethane (designated as R-22) was also a popular refrigerant.
Solvent
The hydrogen attached to carbon in chloroform participates in hydrogen bonding. Worldwide, chloroform is also used in pesticide formulations, as a solvent for fats, oils, rubber, alkaloids, waxes, gutta-percha, and resins, as a cleansing agent, grain fumigant, in fire extinguishers, and in the rubber industry. CDCl3 is a common solvent used in NMR spectroscopy.
Reagent
As a reagent, chloroform serves as a source of the dichlorocarbene :CCl2 group. It reacts with aqueous sodium hydroxide usually in the presence of a phase transfer catalyst to produce dichlorocarbene, :CCl2. This reagent effects ortho-formylation of activated aromatic rings such as phenols, producing aryl aldehydes in a reaction known as the Reimer–Tiemann reaction. Alternatively, the carbene can be trapped by an alkene to form a cyclopropane derivative. In the Kharasch addition, chloroform forms the CHCl2 free radical in addition to alkenes.
Anesthetic
The anaesthetic qualities of chloroform were first described in 1842 in a thesis by Robert Mortimer Glover, which won the Gold Medal of the Harveian Society for that year. Glover also undertook practical experiments on dogs to prove his theories. Glover further refined his theories and presented them in the thesis for his doctorate at the University of Edinburgh in the summer of 1847. The Scottish obstetrician James Young Simpson was one of the persons required to read the thesis, but later claimed to have never read the thesis and to have come to his conclusions independently.
On 4 November 1847, Simpson first used the anesthetic qualities of chloroform on a pair of humans: two guests at his dinner party. This was done as entertainment and not as a medical procedure.
A few days later, during the course of a dental procedure in Edinburgh, Francis Brodie Imlach became the first person to use chloroform on a patient in a clinical context.