含2，4－二硫代乙内酰脲分子片卡宾铁羰基簇合物的合成和结构

Ｆｅ_３（ＣＯ）_（１２）与５个２，４－二硫代乙内酰脲ＳＣＮＨＣ（Ｒ_１）（Ｒ_２）Ｃ（Ｓ）ＮＨ反应制得通式为Ｆｅ_３（ＣＯ）_８（ｕ３－Ｓ）_２（Ｌ）含卡宾配体的５个新铁羰基联合物（１～５），对其进行了元素分析、ＩＲ、~１ＨＮＭＲ和ＭＳ表征，并用Ｘ射线衍射法测定了簇合物３的晶体和分子结构，表明２，４－二硫代乙内酰脲分子片配位基：ＣＮＨＣ（ＣＨ_３）_２Ｃ（Ｓ）ＮＨ的卡宾碳具有ｓｐ~２成键特征，其Ｃ卡宾－Ｆｅ键长０．１８９８ｎｍ，３的分子几何构型维持母体物Ｆｅ_３（ＣＯ）_９（ｕ_３－Ｓ）_２的形状，其中卡宾取代了四方锥分子骨架基底平面Ｆｅ（１）Ｓ（１）Ｆｅ（３）Ｓ（２）的Ｆｅ（１）原子上轴向位置的一个端羰ＣＯ。

Syntheses and Structures of Trinuclear Iron Carbonyl ClustersContaining Carbenes from Cleaving of 2,4-Dithiohydantoins

The reaction of Fe3 (CO )12 with 2 , 4-dithiohydantoins SCNHC(R1) (R2)C(S)NH (SL) yields the known Fe3 (CO)9(u3-S)2 and the five new open triangular iron carbonyl clus ters Fe3(CO)8(u3-S)2(L) 1-5. It was found that the coordinated ligands in the clusters 1-5 besides eight terminal CO ligands are two sulfito S atoms and a heterocyclic carbene L which was formed from the cleavage of the ligand precursor SL. The formulas and structures of these clusters were characterized by elementary analysis, IR, 1H NMR and MS techniques and the molecular structure of 3 was determined by X-ray diffraction analysis. The sp2 bond ing character of the carbon (carbene) atom of fragmental 2,4-dithiohydantoin : CNHC(CH3)2C(S)NH shown clearly in 3 and the Ccarh.-Fe bond length of 0. 1898 nm cor responds to other iron stabilized carbenes. This carbene ligand displaced a terminal axial CO of the basal Fe (1) atom and locates in a vertical position to the Fe (1)S(1)Fe (3)S(2) distort ed basal plane. The geometry of Fe, (CO)9 (u3-S)2 has been maintained in 3, but some of Fe-S and Fe-Fe bond lengths have been changed.