Trigonal-lantern dinuclear compounds of diiron(I,II): the synthesis and characterization of two highly paramagnetic Fe2(amidinato)3 species with short metal-metal bonds
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- 作者：Cotton ; F. Albert ; Daniels ; Lee M. ; Falvello ; Larry R. ; Matonic ; John H. ; Murillo ; Carlos A.
- 关键词：Crystal structures ; Magnetism ; Iron complexes ; Trigonal lantern complexes ; Metal-metal bond complexes ; Dinuclear complexes
- 刊名：Inorganica Chimica Acta
- 出版年：1997
- 出版时间：March 31, 1997
- 年：1997
- 卷：256
- 期：2
- 页码：269-275
- 全文大小：599 K
文摘
Two examples of a new type of trigonal-lantern compound in which a formal Fe23+ unit is bridged by three amidinato groups are formed by reacting FeCl2(HDPhF)2 (HDPhF = N,N′-diphenylformamidine) and FeCl2(HDPhBz)2 (HDPhBz = N,N′-diphenylbenzamidine) with NaEt3BH and methyllithium in THF. The isolated crystalline products, Fe2(amidinato)3, have been structurally characterized by X-ray crystallography at −60°C. Crystal data for Fe2(DPhF)3 (I): monoclinic, space group C2/c,a = 17.154(4), b = 8.255(1), c = 23.400(5) Å, β = 93.38(1)°, Z = 4; and for Fe2(DPhBz)3 · 2C6H6 (II): trigonal, space groupRc, a = 11.237(2), c = 76.510(7) Å, Z = 6. The Fe-Fe bond distances, 2.2318(8) and 2.198(2) Å for compounds I and II, respectively, are the shortest known for any diiron compound. The room temperature magnetic susceptibilities of 7.81 and 7.53 B.M. for I and II and the EPR spectrum of I in a toluene glass (10 K) which shows two signals at g values of 1.99 and 7.94 are consistent with the presence of seven unpaired electrons in an axially symmetric environment.