Boron trichloride is a chemical compound

Chemical compound

A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Chemical compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together...

 with the formula BCl₃. This colorless gas is a valuable reagent in organic synthesis

Organic synthesis

Organic synthesis is a special branch of chemical synthesis and is concerned with the construction of organic compounds via organic reactions. Organic molecules can often contain a higher level of complexity compared to purely inorganic compounds, so the synthesis of organic compounds has...

. It is also dangerously reactive.
Boron reacts with halogens to give the corresponding trihalides. Boron trichloride is, however, produced industrially by direct chlorination

Chlorination

Chlorination is the process of adding the element chlorine to water as a method of water purification to make it fit for human consumption as drinking water...

 of boron oxide and carbon

Carbon

Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...

 at 500 °C.

B₂O₃ + 3 C + 3 Cl₂ → 2 BCl₃ + 3 CO

The synthesis is analogous to the Kroll process

Kroll process

Kroll Process is a pyrometallurgical industrial process used to produce metallic titanium. It was invented by William J. Kroll in Luxembourg. After moving to the United States, Kroll further developed the method for the production of zirconium...

 for the conversion of titanium dioxide to titanium tetrachloride.