Pd[P(iPr)3]z-probably because ( ) is considerably less reactive than (1 b), and because the palladium complexes PdLz have a stronger nucleophilic character than their PtL, analogs.
Procedure
( 2 a ) : A solution of Pd[P(iPr)3]z (114.4mg, 0.77mmol) in toluene (2.5 ml) is added dropwise with stirring to a solution of (1 a ) (56.9mg, 0.77mmol). The reaction mixture changes color from deep-red to orange. On cooling the solution to -30°C orange-yellow crystals are formed. These are recovered by filtration on a G 3 frit, washed with pentane, and dried in a high vacuum. M.p. 64"C, yield 116.5 mg (68 %).-Preparation of (Zb-e) and ( 4 ) analogous to that of ( 2 a ) ; for better crystallization, however, it is recommended that some pentane be added to the toluene solution.
(6a-c): Starting materials analogous to those for ( 2 a ) . For isolation of the product the solvent is removed, the residue treated with pentane, and the resulting solution filtered. On cooling to -30°C yellow crystals are obtained; these are washed with pentane and dried in a high vacuum. Yield 70-90 %.