203569-41-9Relevant articles and documents
Binding of Amino-Dialkylated Adenines to Rhenium(III) and Rhenium(IV) Centers
Pearson, Céline,Beauchamp, André L.
, p. 1242 - 1248 (2008/10/08)
Amino-dialkylated adenines R2AdH (R = Me, Et) react with ReCl3MeCN)(PPh3)2 to form mer,cis-ReCl3(R2-AdH)2(PPh3) complexes. Attempts to protonate the coordinated adenine with HCl led to the oxidized transReCl4(R2AdH)(PPh3) compounds. In both types of complexes, the purine binds via the N3 site of the six-membered ring and makes an intramolecular N9-H?Cl hydrogen bond with a chloride ligand. A material of composition ReCl4(R2AdH)(McCN) was obtained by reacting R2AdH with cis-ReCl4(MeCN)2. It turned out to be a ReCl4[R2-AdC(Me)-NH] complex containing a cyclic amidine ligand resulting from the insertion of the acetonitrile C≡N group in the N9-H bond of the N3-coordinated adenine unit. Crystal structures were determined for one compound of each type: ReCl3(Me2AdH)2(PPh3)·2C 6H5CH3, triclinic, P1, a = 14.181(2) A?, b = 17.591(3) A?, c = 19.015(5) A?, α = 76.66(2)°, β= 86.80(2)°, γ = 87.02(1)°, Z = 4, R = 0.0606; ReCl4(Me2Adh)(PPh3), triclinic, P1?, a = 10.391(4) A?, b= 10.801(5) A?, c= 13.651(6) A?, α = 89.64(4)°, β- 83.49(3)°, γ = 65.14(4)°, Z = 2, R = 0.0432; ReCl4[Me2AdC(Me)-NH]·C6H 6·CH2Cl2, monoclinic, P21/c, a - 13.941(3) A?, b = 13.656(3) A?, c = 12.874(2) A?, β= 105.47(2)°, Z = 4, R = 0.0406. Most of the signals in the 1H NMR spectra of these paramagnetic species could be assigned.
