Effect of phosphoryl and thiophosphoryl groups on CH acidities

It is shown that the CH acidities of phosphoryl and thiophosphoryl compounds depend on the substituents attached to both the carbon atom and the phosphorus atom and comply with Hammett dependences; the parameters of the correlation dependences are very close for the two types of compounds, and this makes it possible to propose a general equation for calculating the pK values of CH acids that contain a phosphoryl or thiophosphoryl group.A. N. Nesmeyanov Institute of Heteroorganic Compounds, Academy of Sciences of the USSR, Moscow. Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 27, No. 3, pp. 284–288, May–June, 1991. Original article submitted February 18, 1991.