Phosphaalkyne

In chemistry, phosphaalkynes (IUPAC name: alkylidynephosphanes) are organophosphorus compounds that have a phosphorus-carbon triple bond, giving them a general formula of (R-C≡P). In chemistry, phosphaalkynes (IUPAC name: alkylidynephosphanes) are organophosphorus compounds that have a phosphorus-carbon triple bond, giving them a general formula of (R-C≡P). Phosphaalkynes are heavy structural analogues of nitriles (R-C≡N), i.e. P replaces N in a nitrile. Their reactions are more similar to those of alkynes than nitriles, for example undergoing 1,2-addition reactions and cycloaddition reactions. The presence of the phosphorus lone pair allows then to act as ligands, with their organometallic chemistry being the subject of significant study. Illustrative of the ease of the cyclization reactions, CpCo(C2H4)2 reacts below room temperature with t-BuCP to give good yields of CpCo(P2C2(t-Bu)2). Under properly chosen conditions, phosphaalkynes readily undergo oligomerizations. Uncontrolled thermal reactions give rise to mixtures of cage compounds, whereas metal-mediated phosphaalkyne oligomerizations allow increased control. In 1950, H. Albers reported the first indication of the existence of H-C≡P. This compound was identified by infrared absorption spectrometry, and its synthesis was improved by Manfred Regitz in 1987. The synthesis of the first kinetically stable phosphaalkyne, tert-Butylphosphaacetylene), was reported in 1981 by Gerd Becker and Werner Uhl.