Organophosphanes

Methylidynephosphane (phosphaethyne) is a chemical compound with the chemical formula . It was the first phosphaalkyne compound discovered, containing the unusual C≡P carbon-phosphorus triple bond. Although isolated samples of methylidynephosphane are impractical, other derivatives have been well studied such as tert-butylphosphaacetylene. The conjugate base of methylidynephosphane is cyaphide.

thumb|right|The structure of a typical phosphorane group. A phosphorane (IUPAC name: λ5-phosphane) is a functional group in organophosphorus chemistry with pentavalent phosphorus. Phosphoranes have the general formula PR5.

thumb|right|Molecular structure of , a phosphaalkyne.

chemical compound

Organophosphines are organophosphorus compounds with the formula PRnH3−n, where R is an organic substituent. These compounds can be classified according to the value of n: primary phosphines (n = 1), secondary phosphines (n = 2), tertiary phosphines (n = 3). All adopt pyramidal structures. Organophosphines are generally colorless, lipophilic liquids or solids. The parent of the organophosphines is phosphine (PH3).