TY - JOUR
T1 - On the nature and mechanism of decomposition of monovalent copper complexes with tetra-aza macrocyclic ligands in aqueous solutions. A pulse radiolytic study
AU - Freiberg, Mira
AU - Meyerstein, Dan
AU - Yamamoto, Yasuo
N1 - Funding Information:
when going from [CuL1]+ (tetrahedral)to [CuL4]+ (tetrahedral) suggests that the copper in thelatter complex is a weaker reducing agent, again inagreement with expectation4 as the larger ring is ex-pected better to accommodate the monovalent copperand to enable a better interaction of the d orbitals withthe x* orbitals of the ligand. However, we note sur-prisingly that k , (L4) is considerably lower than k, forthe other complexes. This is unexpected if [CuL4]2+ isthe strongest oxidant, as expected from the results inalcohol solutions4 and from the known effects of ringsize on the electrochemistry of macrocyclic complexesin aprotic media. 'One might speculate that the largerring size enables a better hydration of the planar [CuL4]2+complex and thus stabilizes it.[CUL3]+.This study was supported in part by grants from theP.R.F., the United States Israel Binational Science FoundJ. CHEM. SOC. DALTON TRANS. 1982 1141ation (B.S.F.), Jerusalem, Israel and by the Israel Commis-sion for Basic Research.[ 1 / 1663 Received, 26th October, 198 13REFERENCES19, 1908.stein, J . Chem. SOL, Faraday Trans. 1, 1980, 1838.Trans. 1, 1980, 1825.M. Freiberg, J . Lilie, and D. Meyerstein, Inorg. Chem., 1980,M. Freiberg, W. A. Mulac, K. H. Schmidt, and D. Meyer-3 M. Freiberg and D. Meyerstein, J . Chem. SOC., FaradayY. Yamamoto, T. Sasaki, T. Izumidani, and T. Kurata,M. S. Matheson and L. M. Dorfman, ' Pulse Radiolysis,'M. Anbar, M. Bambenek, and A. B. Ross, Nut. Stand. Ref.L. M. Dorfman and G. E. Adams. Nal. Stand. Ref. DataM. Anbar, Farhataziz, and A. B. Ross, Nat. Stand. Ref.D. Meyerstein, Inorg. Chem., 1975, 14, 1716.Inorg. Nztcl. Chem. Lett., 1978, 14, 239.M.I.T. Press, Cambridge, Mass., 1969.Data Ser., Nut. Bur. Stand., 1973, 43.Ser., Nut. Bur. Stand., 1973, 46.Data Ser., Nat. Bur. Stand., 1975, 51
PY - 1982/1/1
Y1 - 1982/1/1
N2 - Some properties of four monovalent copper complexes with tetra-azamacrocyclic ligands (L) are reported. For all four complexes the same sequence of rearrangement and ligand loss (five reactions) is observed. The rates of rearrangement and ligand loss increase with increasing size of the macrocycle and by using 1,4,8,11-tetra-azacyclotetradecane in place of 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetra-azacyclotetradecane. The introduction of two non-conjugated double bonds has little effect on the rates of reaction but affects considerably the spectra of the [CuL]+ complexes.
AB - Some properties of four monovalent copper complexes with tetra-azamacrocyclic ligands (L) are reported. For all four complexes the same sequence of rearrangement and ligand loss (five reactions) is observed. The rates of rearrangement and ligand loss increase with increasing size of the macrocycle and by using 1,4,8,11-tetra-azacyclotetradecane in place of 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetra-azacyclotetradecane. The introduction of two non-conjugated double bonds has little effect on the rates of reaction but affects considerably the spectra of the [CuL]+ complexes.
UR - http://www.scopus.com/inward/record.url?scp=0039576986&partnerID=8YFLogxK
U2 - 10.1039/DT9820001137
DO - 10.1039/DT9820001137
M3 - Article
AN - SCOPUS:0039576986
SN - 1472-7773
SP - 1137
EP - 1141
JO - Journal of the Chemical Society. Dalton Transactions
JF - Journal of the Chemical Society. Dalton Transactions
IS - 6
ER -