Metal Complexes of Diethyl Phenylphosphonite

The complex [Ni P(OC6H5)3 4] can be handled in air. The compound is insoluble in polar solvents and only slightly soluble in hydrocarbons. 

Submitted by D. TITUS, A. A. OHIO, and HARRY B. GRAY Checked by G. W. PAR SIIALLt and J. J. MROWCAf 

The diethyl ester of phenylphosphonous acid (diethoxyphenyl-phosphine) provides an easy pathway to relatively stable telrakis complexes of zero- and low-valent transition metals.1,2 Anhydrous metal halides serve as the metal source for the complexes, avoiding the necessity of inconvenient starting materials such as nickel carbonyl. The nickel(O) complex is formed by reaction with the phosphonite in ethanol with the addition of sodium tetrahydroborate, relatively stable dihydridoiron(l I) and hydridocobalt(I) complexes are obtained. 

The phosphonite is prepared from inexpensive starting materials, following the method of Rabinowitz and Pcllon 3 

This reaction is conveniently carried out in a 2-1., three-necked flask with 143 g. phenylphosphonous dichloride (0.8 mole), 74 g. absolute ethanol (1.6 moles), 163 g. triethylamine (1.6 moles), and 700 ml. benzene. The yield of water-white product is about 100 g. (63%). It is soluble in most organic solvents and slowly reacts with air it should be stored under nitrogen. Its infrared spectrum has been reported.4 

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