Preparation and reactions of tetrahedrane-type clusters containing a SCoFeM (M = Mo or W) core.: The single crystal X-ray structure of the cluster (μ-S)CoFeMo(CO)8[η5-C5H4C(O)CH2CH2CO2Me]

Treatment of the monoanions {M(CO)(3)[eta (5)-C5H4C(O)CH2CH2CO2Me]} - with FeCo2(CO)(9)(mu (3)-S) in refluxing THF gave the novel cluster complexes (mu (3)-S)CoFeM(CO)(8)[eta (5)-C5H4C(O)CH2CH2CO2Me] (M = Mo, 1; M = W, 2). Reactions of the cluster (mu (3)-S)CoFeMo(CO)(8)[eta (5)-C5H4C(O)Me] (3) with amine derivatives 2,4-dinitrophenylhydrazine, thiosemicarbazide, (-)-5-(alpha -phenyl)semioxamazide and L-(+)-menthydrazide respectively at room temperature yielded four new hydrazone cluster complexes (mu (3)-S)CoFeMo(CO)(8)[eta (5)-(C5HC)-C-4(NR)Me] [4-7, R= NHC6H3-2,4-(NO2)(2), NHC(S)NH2, NHC(O)C(O)NHCH(Me)(C6H5) and NHCO2(menthyl)]. However, cluster 1 only reacted with 2,4-dinitrophenylhydrazine to give the cluster (mu (3)-S)CoFeMo(CO)(8)[eta (5)-C5H4C(NR)Me] [8, R = NHC6H3-2,3-(NO2)(2)] under the same conditions. Although two kinds of optically active groups have been attached to the racemic cluster, the mixture of diastereoisomers produced cannot be separated chromatographically. The C-13 NMR showed the presence of the diastereoisomers of clusters 5 and 6. Cluster 1 has been solved by single-crystal X-ray diffraction. (C) 2001 Elsevier Science Ltd. All rights reserved.