Abstract
Reaction of Co(CIO 4) 2 with 1,5,9,13-tetraazacycgohexadecane ([16]aneN 4) resulted in the formation of a new tetrahedtal Co(ll) complex, [Co([16] aneN 4)] (CIO 4)2 ( 2). Compound 2 isomerized into a more stable tetragonal complex, [Co([16]aneN 4)(Cl0 4) 2] ( 3), with two CIO 4 − anions coordinated to Co 2+ at the axial positions. Compound 2 reacted with one equivalent of Br − to form a square-pyramidal complex, [Co([16]aneN 4)Br(CIO 4)] ( 4), in which a CIO 4 − anion is weakly coordinated to Co 2+. The Br − anion in 4 can be removed with AgCIO 4 in MeOH to convert 4 back into 2. When the dehalogenatiou reaction was carried out in water using AgNO 3, in addition to the expected product, [Co([16]aneN 4)](CIO 4)(NO 3) ( 2′), a new tetragonal complex, [Co([16]aneN 4)(H 2O) 2](CIO 4)(NO 3)( 5), was also isolated. In the presence of py, compound 2 was converted into [Co([16]aneN 4)(py)(CIO 4)](CIO 4)( 6). Compounds 2–6 were characterized by X-ray crystallography. 2 crystallized in the monoclinic space group P2 1 ln with cell dimensions (20°C) of α=8.632(2) A ̊ , b = 13.936(1) A ̊ , c = 17.092(3) A ̊ , β=90.08(2) °, V= 2056.1(6) A ̊ 3 and Z=4. 3 crystallized in the monoclinic space group P2 n with cell dimensions (20°C) of α= 14.207(2) A ̊ ,b= 10.1415(8) A ̊ ,c= 14.707(3) A ̊ , β= I 11.97(1) °, V = 1965,1(5) A ̊ 3 and Z=4. 4 crystallized in the monoclinic space group P2 1 n with cell dimensions (20°C) of a = 7.977(1) A ̊ , b = 24.548(2) A ̊ , c=9.781 (2) A ̊ , β = 104.89(1) °, V = 1851.0(5) A ̊ 3 and Z=4 . 5 crystallized in the monoclinic space group P2 1 n with cell dimensions (−50°C) of a=9.623(2) A ̊ , b= 13.305(2) A ̊ , c= 16.530(2) A ̊ , β= 103.23(2)°, V= 2060.2(8) A ̊ 3 and Z=4. 6 crystallized in the tetragonal space group I4 a with cell dimensions (−60°C) of a = 12.6822(5) A ̊ , c=60.296(3) A ̊ , V=9697.9(7) A ̊ 3 and Z= 16 .
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call