Tetrakis triethyl phosphite palladium O

A concentrated solution of potassium tetrachloropalladate(II), K2[PdCl4] (0.330 g, 0.001 mol), is prepared by dissolving it in a minimum amount ( 2.5mL) of water at room temperature. A methanol (3mL) solution of triethyl phosphite (0.831 g, 0.005 mol) is placed in a test tube containing a small stirring bar. The triethyl phosphite (Matheson, Coleman and Bell) was distilled before use and kept under nitrogen (bp 77°, 25 mm). 

The dry product, [Pd P(OC2H5)3 4], containing no adsorbed triethyl phosphite is air sensitive, turning black on exposures to air exceeding a few minutes. It should be handled in an inert atmosphere (glove box or a large beaker filled with argon). It is stored in an evacuated and sealed tube. The complex is insoluble in water, soluble in methanol, and very soluble in hydrocarbons, in which it does not dissociate. 

The platinum(O) compound can be prepared by a method analogous to that of Malatesta and Cariello. Powdered potassium hydroxidef (0.350-0.400 g, 0.006 mol) is dissolved in 10 mL of methanol contained in a large test tube (about 1-in. diameter). To this is added triethyl phosphite (2.5 g, 0.015 mol) and a small stirring bar, and then the test tube is placol in an oil bath kept at 

75° by a heater-stirrer plate. When the solution in the test tube has reached the temperature of 60°, a solution of potassium tetrachloroplatinate(II), KjCPtC ] (1.24 g, 0.(X)3 mol), in about 20 mL of water is slowly added with stirring. Immediately or within a few minutes, colorless crystals separate. The crystals are collected on a glass frit, washed with a few milliliters of an ethanol-water mixture (50% by volume), and dried under vacuum for 4 h at room temperature. Yields vary from 0.45 to 0.58 g (52-67%), mp 114°. 

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