PLATINUM(II) TEMPLATE SYNTHESIS OF A PENDANT-ARM MACROCYCLE

Platinum(II)-directed condensation of ethane-1,2-diamine with nitroeth ane and formaldehyde yields the colourless macrocyclic complex ro-1,4, 8,11-tetraazacyclotetradecane)platinum(II), [Pt(1)](2+), in good yield . This parallels chemistry reported earlier around other triad members nickel(II) and palladium(II). The pendant nitro groups in the major i somer are disposed on opposite sides of the macrocycle in a trans geom etry, as confirmed by the X-ray crystal structure analysis of [Pt(1)] (ClO4)(2), which crystallizes in the triclinic space group P (1) over bar, a 8.041(4), b 8.482(4), c 9.443(3) Angstrom, alpha 69.44(3), beta 67.66(4), gamma 71.73(4)degrees, Z 1, and was refined to an R value o f 0.027 on 1920 F. The platinum ion lies in a square planar environmen t of four nitrogen donors, with typical Pt-N distances; comparisons be tween the platinum(II) and palladium(II) complexes of (1) and its anal ogue (2), with diammonio groups in place of dinitro groups, are discus sed.