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 PdI(2) and PtI(2), these isocyanides form the complexes trans-[MI(2)(CNR)(2)], 12-19 (M = Pd, Pt; CNR = 3, 6, 9, 11). The previously prepared complex trans-[PdI(2)(CNC(5)H(4)N-3)(2)] and trans-[PdI(2)(CNC(6)H(2)-(i-Pr)(2)-2,6-(CC-C(5)H(4)N-4)-4)(2)], 16, combine with copper bis(trifluoroacetylacetonate) in the ratio of 1:2 to form the adducts trans-[PdI(2)(CNC(5)H(4)N-3)(2)].2[Cu(tfacac)(2)].2CH(2)Cl(2), 20, and trans-[PdI(2)(CNC(6)H(2)-(i-Pr)(2)-2,6-(CC-C(5)H(4)N-4)-4)(2)].2[Cu(tfacac)(2)], 21, respectively. The complexes trans-[MI(2)(CNC(6)H(2)-(i-Pr)(2)-2,6-(C(5)H(4)N-4)-4)(2)], 19 (M = Pd) and 20 (M = Pt), react with [Pd(SO(3)CF(3))(2)(dppp)] (dppp = bisdiphenylphosphinopropane) to form the molecular squares [Pd(dppp)(trans-[MI(2)(CNC(6)H(2)-(i-Pr)(2)-2,6-(C(5)H(4)N-4)-4)(2)](4)(SO(3)CF(3))(8), 22 (M = Pd) and 23 (M = Pt). The crystal structure of 20 has been determined by X-ray crystallography. 20: C(34)H(28)Cl(4)Cu(2)F(12)I(2)N(4)O(8)Pd, monoclinic space group, P2(1)/n (No. 14), a = 10.899(3) Å, b = 13.903(1) Å, c = 17.827(6) Å, beta = 105.50(2) degrees, Z = 2, 2618 unique reflections, R = 0.093, R(w) = 0.091.