Phosphorus triiodide

Phosphorus (III ) iodide

Red solid

Fixed

4.18 g · cm -3

61 ° C

Decomposition in water

Risk

Template: Infobox chemical / molecular formula search is not possible

Phosphorus triiodide is a chemical compound with the formula PI3. It consists of a central phosphorus atom is symmetrically surrounded by three iodine atoms. The compound is tetrahedrally constructed as phosphorus or has a free electron pair in the 3 oxidation state, which is the fourth vertex of the tetrahedron.

Representation

The synthesis of phosphorus triiodide can be achieved by the reaction of white phosphorus and elemental iodine in carbon disulfide.

Properties

Phosphorus triiodide is a red solid, which melts at 61 ° C at room temperature. The bond length between phosphorus and iodine is 243 pm, the I- P- I bond angle is 102 °.

Use

Phosphorus triiodide can be employed for the synthesis of alkyl iodides from the corresponding alcohols. As can be obtained from methanol in this manner, for example, methyl iodide.