摘要
Addition of the Lewis base [OPh] - to the THF solution of Roussin's red ester [Fe(μ-SC 6 H 4 -o-NHCOPh)(NO) 2 ] 2 (1) and [Fe(μ-SC 6 H 4 -o-COOH) (NO) 2 ] 2 (2), respectively, yielded the EPR-active, anionic {Fe(NO) 2 } 9 , [(SC 6 H 4 -o-NCOPh)-Fe(NO) 2 ] - (3) with the anionic [SC 6 H 4 -o-NCOPh] 2- ligand bound to the {Fe(NO) 2 } core in a bidentate manner (S,N-bonded) and [(SC 6 H 4 -o-COO) Fe(NO) 2 ] - (4) with the anionic [SC 6 H 4 -o-COO] 2- ligand bound to the {Fe(NO) 2 } core in a bidentate manner (S,O-bonded), characterized by IR, UV-vis, EPR, and single-crystal X-ray diffraction. In contrast to the bridged-thiolate cleavage yielding the neutral {Fe(NO) 2 } 9 , [(SC 6 H 4 -o-NHCOPh)(Im)Fe(NO) 2 ] (Im = imidazole), by addition of 2 equiv of imidazole to complex 1 observed in the previous study, the addition of the stronger σ-donating and π-accepting PPh 3 ligand triggered the reductive elimination of bridged thiolates of complex 1 to yield the neutral {Fe(NO) 2 } 10 , [(PPh 3 ) 2 Fe(NO) 2 ]. These results unambiguously illustrate one aspect of how the nucleophile L (L = imidazole, PPh 3 , [OPh] - ) functions to control the reaction pathways (bridged-thioiate cleavage, reductive elimination, and deprotonation) upon the reaction of complex 1 and the nucleophile L. The EPR-active, dimeric {Fe(NO) 2 } 9 dinitrosyl iron complex (DNIC) [Fe(μ-SC 7 H 4 SN)(NO) 2 ] 2 (6), with S and N atoms of the anionic [-SC 7 H 4 SN-] _ (2-benzothiozolyl thiolate) ligands bound to two separate {Fe(NO) 2 } 9 cores, was also synthesized from reaction of bis(2-benzothiozolyl) disulfide and [(NO) 2 Fe(PPh 3 ) 2 ]. A straightforward reaction of complex 6 and 4 equiv of [N 3 ] - conducted in THF led to the anionic {Fe(NO) 2 } 9 , [(N 3 ) 2 Fe(NO) 2 ] - (7). Conclusively, the EPR-active, {Fe(NO) 2 } 9 DNICs can be classified into the anionic {Fe(NO) 2 } 9 DNICs with S/N/O ligation, the neutral {Fe(NO) 2 } 9 DNIC with one thiolate and one neutral imidazole ligation, and the cationic {Fe(NO) 2 } 9 DNICs with the neutral N-/P-containing coordinated ligands. © 2007 American Chemical Society.