PALLADIUM(II) AND PLATINUM(II) COMPLEXES WITH NUCLEOBASES AND NUCLEOSIDES - CRYSTAL-STRUCTURE OF TRANS-BIS(ADENINATO)BIS(TRI-N-BUTYLPHOSPHINE)PALLADIUM(II)

The synthesis and degradation of the dinuclear and tetranuclear complexes IL(n-Bu3P)MC1]2 and [C12(m-Bu3P)M(L)-M(P-n-Bu3)C1]2 [M=Pd(II), Pt(II)] with the anion of adenine (L) have been studied. A series of complexes trans-(n-Bu3P)2PdL2 and [L(n-Bu3P)PdCl]„ with L =adeninate, cytosinate, guaninate, guanosinate, inosinate, theophyllinate, thyminate, uracilate, and uridinate, as well as adenosine-bridged complexes Cl2(n-Bu3P)M-adenosine-M(P-n-Bu3)Cl2 [M =Pd,Pt], have been synthesized. The spectroscopic data of the new complexes are reported. Crystals of trans-(n-Bu3P)2Pd(adeninate)2'4CH3OH are triclinic (space group P$$) with the cell parameters a=10.993 (2) υ, b=11.945 (2) υ, c=10.140 (2) υ,a =105.36 (1)°, β=91.80 (1)°, and γ=93.16 (1)°. The structure was refined to=0.045 and R2=0.051. The X-ray structure determination shows that adeninate is coordinated via N(9) and that the purine rings are virtually orthogonal to the coordination plane P2PdN2. The colorless crystals are stabilized by hydrogen bonds between the oxygen atoms of the methanol molecules and N(3) and N(7) of adenine. Intermolecular hydrogen bonding is observed between the amino group N(6)H2 and N”(l). Thus, with the exception of the metalated N(9) atom all of the adeninate N atoms are involved in hydrogen bonding. © 1979, American Chemical Society. All rights reserved.