名称:
Synthetic and Structural Investigations on Some New 1,2,4,5-(CH2)4C6H2 Moiety-Containing Butterfly Fe/S Cluster Complexes from Reactions of Tetrathiol 1,2,4,5-(HSCH2)4C6H2 with Fe3(CO)12 or with Fe3(CO)12 in the Presence of Et3N
摘要:
The 1,2,4,5-(CH2)(4)C6H2 moiety-containing butterfly Fe/S complexes [1,2-(CH2S2CH2)-4,5-(mu-SCH2)(2)C6H2][Fe-2(CO)(6)] (1), [1,2,4,5-(mu-SCH2)(4)C6H2][Fe-2(CO)(6)](2) (2), and [(1,2-Me-2)-4,5-(mu-SCH2)(2)C6H2][Fe-2(CO)(6)] (3) have been prepared by the reaction of tetrathiol 1,2,4,5-(HSCH2)(4)C6H2 with Fe-3(CO)(12) under different conditions. Treatment of complex 1 with PPh3 or PMe3 in the presence of Me3NO or with the in situ generated N-heterocyclic carbene I-Mes (I-Mes = 1,3-bis(mesityl)imidazol-2-ylidene) afforded the corresponding monosubstituted single-butterfly complexes [1,2-(CH2S2CH2)-4,5-(mu-SCH2)(2)C6H2][Fe-2(CO)(5)L] (4, L = PPh3; 5, L = PMe3; 6, L = I-Mes). However, in contrast to the above-mentioned reaction of tetrathiol 1,2,4,5-(HSCH2)(4)C6H2 with Fe-3(CO)(12), the reactions of 1,2,4,5-(HSCH2)(4)C6H2 with Fe-3(CO)(12) in the presence of Et3N, followed by treatment with PhCOCl or PhC(Cl)=NPh, resulted in formation of the quadruple- and triple-butterfly complexes [(mu-PhC=O)Fe-2(CO)(6)](4)[1,2,4,5-(mu-SCH2)(4)C6H2] (7) and [(mu-PhC=NPh)Fe-2(CO)(6)](2)[Fe-2(CO)(6)][1,2,4,5-(mu-SCH2)(4)C6H2] (8), whereas the same tetrathiol reaction system reacted with PhC CH to give quadruple- and triple-butterfly complexes [(mu-sigma,pi-PhCH=CH)-Fe-2(CO)(6)](4)[1,2,4,5-(mu-SCH2)(4)C6H2] (9) and [(mu-sigma,pi-PhCH=CH)Fe-2(CO)(6)](2)[Fe-2(CO)(6)][1,2,4,5-(mu-SCH2)(4)C6H2] (10). More interestingly, the dithioformato ligand-containing quadruple-butterfly complex [(mu-S=CSCH2Ph)Fe-2(CO)(6)](4)[1,2,4,5-(mu-SCH2)(4)C6H2] (11) could be prepared by the reaction of the tetrathiol system with CS2, followed by treatment with PhCH2Br, but the same tetrathiol/CS2 system reacted with CpFe(CO)(2)I to afford the triple-butterfly complex [(mu-S=CSFe(CO)(2)Cp)Fe-2(CO)(6)](2)[Fe-2(CO)(6)][1,2,4,5-(mu-SCH2)(4)C6H2] (12). The possible pathways for production of complexes 1-3 and 7-12 are proposed, and the suggested intermediate [1,2-(HSCH2)(2)-4,5-(mu-SCH2)(2)C6H2][Fe-2(CO)(6)] (M-6) for formation of complex 1 has been successfully isolated under anaerobic conditions. The structures of complexes 1, 3, 4, 8, 9, and 11 have been confirmed by X-ray crystallography.