Synthesis and Characterization of the first Copper(II) Complex of 6‐Azathymine. The Crystal Structure of [[CuCl 2 (H 2 O) 2 (AT)} 2 ] · 2H 2 O; (AT = 6‐Azathymine)

The reaction of 3, 4‐dihydro‐6‐methyl‐3‐thioxo‐1, 2, 4‐triazin‐5(2H)‐one (6‐aza‐2‐thiothymine, AAT, 1 ) with copper(I) chloride in presence of hydrochloric acid in methanol gives the complex [{CuCl 2 (H 2 O) 2 (AT)} 2 ] · 2H 2 O, 2 , AT = 6‐azathymine) in excellent yield. 2 was characterized by IR spectroscopy and elemental analyses as well as mass spectrometry. Also single‐crystal X‐ray diffraction studies on compound 2 revealed that AT acts as a monodentate ligand in the centrosymmetric binuclear complex via its oxygen atom. Crystal data for 2 at —80 °C: space group P2 1 /c with a = 550.1(1), b = 2712.5(1), c = 729.7(1) pm, β = 95.99(1)°, Z = 2, R 1 = 0.0213.