摘要
Seven square planar bis(o-diiminobenzosemiquinonato)nickel(II) complexes, [Ni(o-C6H4(NH)(NAr))2] (Ar= Mes, 1; p-F-C6H4, 2; p-CI-C6H4, 3), [Ni(o-4,5-F2-C6H2(NH)(NPh))2] (4), and [Ni(o-4,5-CIz-C6H2(NH)(NAr))2] (Ar =Ph, 5; 2,6-F2-C6H3, 6; 2,6-C12-C6H3, 7), have been synthesized and characterized by 1H NMR, 13C NMR, 19F NMR, IR, UV-Vis-NIR, elemental analyses, HRMS, as well as single-crystal X-ray diffraction studies (1 and 7). The cyclic voltammograms of these complexes exhibit two reversible redox processes of [NiLe]0n- and [NIL2]l /2 , and one irreversible process of [NiL2]~n+. Substituent effects on the redox properties of these complexes, in addi- tion with those of the known complexes [Ni(o-C6Ha(NH)(NPh))2] (8) and [Ni(o-3,5-Butz-C6Hz(NH)2)2] (9), are identified by comparing the half-wave potentials of the reduction waves, as 1 ~ 9 〈 8 ~ 2 〈 3 〈 4 〈 5 〈 7 〈 6, reflect- ing the ease of reduction of [NIL2] parallels the electron-donating and -withdrawing ability of the substituent group. Reduction of 1 with one or two equivalents of sodium metal in THF has led to the isolation of [Na(THF)3][I] and [Na(THF)3]2[1]. The structure data of these two complexes revealed by low-temperature X-ray crystallography suggest their corresponding electronic structures of [Nill(lL-1 )(IL2-)]1- and [Ni1](1L2 )212-, which are in line with those of [9]n (n = 1-, 2-) suggested by spectroelectrochemical study.
Seven square planar bis(o-diiminobenzosemiquinonato)nickel(II) complexes, [Ni(o-C6H4(NH)(NAr))2] (Ar= Mes, 1; p-F-C6H4, 2; p-CI-C6H4, 3), [Ni(o-4,5-F2-C6H2(NH)(NPh))2] (4), and [Ni(o-4,5-CIz-C6H2(NH)(NAr))2] (Ar =Ph, 5; 2,6-F2-C6H3, 6; 2,6-C12-C6H3, 7), have been synthesized and characterized by 1H NMR, 13C NMR, 19F NMR, IR, UV-Vis-NIR, elemental analyses, HRMS, as well as single-crystal X-ray diffraction studies (1 and 7). The cyclic voltammograms of these complexes exhibit two reversible redox processes of [NiLe]0n- and [NIL2]l /2 , and one irreversible process of [NiL2]~n+. Substituent effects on the redox properties of these complexes, in addi- tion with those of the known complexes [Ni(o-C6Ha(NH)(NPh))2] (8) and [Ni(o-3,5-Butz-C6Hz(NH)2)2] (9), are identified by comparing the half-wave potentials of the reduction waves, as 1 ~ 9 〈 8 ~ 2 〈 3 〈 4 〈 5 〈 7 〈 6, reflect- ing the ease of reduction of [NIL2] parallels the electron-donating and -withdrawing ability of the substituent group. Reduction of 1 with one or two equivalents of sodium metal in THF has led to the isolation of [Na(THF)3][I] and [Na(THF)3]2[1]. The structure data of these two complexes revealed by low-temperature X-ray crystallography suggest their corresponding electronic structures of [Nill(lL-1 )(IL2-)]1- and [Ni1](1L2 )212-, which are in line with those of [9]n (n = 1-, 2-) suggested by spectroelectrochemical study.
基金
We thank the financial supports from the National Natural Science Foundation of China,the Science and Technology Commission of Shanghai Municipality