The isocyanides 3-(4-pyridylethynyl)phenylisocyanide, 3, 4-(4-pyridylethynyl)phenylisocyanide, 6, 2,6-diisopropyl-4-(4-pyridylethynyl)phenylisocyanide, 9, and 2,6-diisopropyl-4-(4-pyridyl)phenylisocyanide 11, were prepared. With PdI2 and PtI2, these isocyanides form the complexes trans-[MI2(CNR)(2)], 12-19 (M = Pd, Pt; CNR = 3, 6, 9, 11). The previously prepared complex trans-[PdI2(CNC5H4N-3)(2)] and trans-[PdI2(CNC5H2-(i-Pr)(2)-2,6-(CC-C5H4N-4)-4)(2)], 16, combine with copper bis(trifluoroacetylacetonate) in the ratio of 1:2 to form the adducts trans[PdI2(CNC5H4N-3)(2)]. 2[Cu(tfacac)(2)]. 2CH(2)Cl(2), 20, and trans-[PdI2(CNC6H2-(i-Pr)(2)-2,6-(CC-C5H4N-4)-4)(2)]. 2[Cu(tfacac)(2)], 21, respectively. The complexes trans-[MI2(CNC6H2-(i-Pr)(2)-2,6-(C5H4N-4)-4)(2)], 19 (M = Pd) and 20 (M = Pt), react with [Pd(SO3CF3)(2)(dppp)] (dppp = bisdiphenylphosphinopropane) to form the molecular squares [Pd(dppp)(trans-[MI2(CNC6H2-(i-Pr)(2)-2,6-(C5H4N-4)-4)(2)](4)(SO3CF3)(8), 22 (M = Pd) and 23 (M = Pt). The crystal structure of 20 has been determined by X-ray crystallography. 20: C34H28Cl4Cu2F12I2N4O8Pd, monoclinic space group, P2(1)/n (No. 14), a = 10.899(3) Angstrom, b = 13.903(1) Angstrom, c = 17.827(6) Angstrom, beta = 105.50(2)degrees, Z = 2, 2618 unique reflections, R = 0.093, R-w = 0.091.