Boron trifluoride

• Trifluoroborane
• Fuman
• Boron (III ) fluoride

• 7637-07-2
• 13319-75-0 (dihydrate )

A colorless, pungent, Smoking in moist air gas

Gaseous

• 3.1 g · l-1
• 1.636 g · cm -3 ( 25 ° C, dihydrate)

-127.1 ° C

-100.4 ° ​​C

Reacts violently with water

0

1.316 (20 ° C, dihydrate)

Risk

2.5 mg · m -3 ( fluoride)

-1136.0 (8) kJ / mol

Template: Infobox chemical / molecular formula search available

Boron trifluoride is a chemical compound consisting of the elements boron and fluorine. It has the molecular formula BF3 and is sometimes also referred to as trifluoroborane.

Production and representation

Boron trifluoride can be recovered by:

• Reaction of boron oxide with hydrofluoric acid:

• A large industrial area by heating diboron trioxide or borax with calcium fluoride and concentrated sulfuric acid
• In the laboratory by thermolysis of diazonium tetrafluoborates
• More of either potassium or sodium tetrafluoroborate and boron trioxide

• Or fluorosulphonic and boric acid:

Properties

Boron trifluoride forms a trigonal planar molecular structure. It is a very toxic, gaseous at room temperature chemical compound that has a critical temperature of -12.3 ° C..

Boron trifluoride is a very strong Lewis acid. It forms addition compounds with electron donors.

With water it reacts with decomposition to boric acid and hydrofluoric acid. In contrast to other boron trihalides no direct hydrolysis takes place, but a sequence of several reactions. Initially formed due to the strong binding BF3 a Lewis acid - base adduct.

However, the hydrolysis is not complete, in contrast to other boron halides, as well as inert, tetrahedral tetrafluoroborate ion ( BF4 - ) is formed.

The products of the hydrolysis reaction further to tetrafluoroboric acid, which is present as an oxonium salt.

Use

In the chemical industry, boron trifluoride can be used for a variety of chemical reactions as a catalyst or a starting material for production of various boron compounds. Gaseous boron trifluoride and boron trifluoride adducts are mainly used as catalysts or co- catalysts, for example in the manufacture of polymers, high-quality lubricating oils, pharmaceuticals, flavors and fragrances, and other fine chemicals and the synthesis of boron compounds such as boranes, amineboranes and reagents Suzuki coupling. Furthermore, it is used in the semiconductor industry for ion implantation Borlieferant (p- doping), to the surface treatment of steel and glass, and in the neutron detectors.

Safety

Boron trifluoride is highly toxic and highly corrosive.

Important BF3 adducts

• BF3 - methanol
• BF3 - phenol
• BF3 - dibutyl
• BF3 - diethyl
• BF3 - dimethyl
• BF3 -THF (tetrahydrofuran )
• BF3 - acetic acid
• BF3 - acetonitrile
• BF3 dihydrate
• BF3 - phosphoric acid