Bromofluoromethane
Encyclopedia
Bromofluoromethane is a mixed gaseous halomethane
Halomethane
Halomethane compounds are derivatives of methane with one or more of the hydrogen atoms replaced with halogen atoms . Halomethanes are both naturally occurring, especially in marine environments, and man-made, most notably as refrigerants, solvents, propellants, and fumigants...

 soluble in alcohol
Alcohol
In chemistry, an alcohol is an organic compound in which the hydroxy functional group is bound to a carbon atom. In particular, this carbon center should be saturated, having single bonds to three other atoms....

 and very soluble in chloroform
Chloroform
Chloroform is an organic compound with formula CHCl3. It is one of the four chloromethanes. The colorless, sweet-smelling, dense liquid is a trihalomethane, and is considered somewhat hazardous...

.

Its standard molar entropy
Standard molar entropy
In chemistry, the standard molar entropy is the entropy content of one mole of substance, under standard conditions ....

, Sogas is 276.3 J/(mol K) and heat capacity
Heat capacity
Heat capacity , or thermal capacity, is the measurable physical quantity that characterizes the amount of heat required to change a substance's temperature by a given amount...

, cp is 49.2 J/(mol K).

Preparation

Up to date, it has been prepared by three prevailingly ineffective methods:
  1. From salts of fluoroacetic acid
    Fluoroacetic acid
    Fluoroacetic acid is a compound with formula H. It is between acetic acid and trifluoroacetic acid....

     using a Hunsdiecker type of reaction.
  2. From dibromofluoromethane
    Dibromofluoromethane
    Dibromofluoromethane is a mixed halomethane. It is soluble in alcohol, acetone, benzene and chloroform.It can be used to prepare bromofluoromethane by reductive debromination with organotin hydride as tributyltin hydride....

     by reductive debromination with a Swarts reagent.
  3. From a dihalomethane by an halogen exchange reaction or from a halomethane by catalyzed bromination
    Halogenation
    Halogenation is a chemical reaction that incorporates a halogen atom into a molecule in substitution of hydrogen atom. Halogenation takes place in the gas phase. There are four types of halogenation: fluorination, chlorination, bromination, and iodination...

     or fluorination
    Halogenation
    Halogenation is a chemical reaction that incorporates a halogen atom into a molecule in substitution of hydrogen atom. Halogenation takes place in the gas phase. There are four types of halogenation: fluorination, chlorination, bromination, and iodination...

    .

The method with the highest yield is reductive debromination of dibromofluoromethane using an organotin hydride.

Uses

Bromofluoromethane is an important reagent in the manufacture of intermediates, pharmaceuticals and other chemicals. Usage of bromofluoromethane is regulated due to its ozone depletion potential
Ozone depletion potential
The ozone depletion potential of a chemical compound is the relative amount of degradation to the ozone layer it can cause, with trichlorofluoromethane being fixed at an ODP of 1.0. Chlorodifluoromethane , for example, has an ODP of 0.055...

(0.73). Its isotopomer CH2Br18F is used in radiochemistry.

External sources

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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