By the reactions of [Rh2Co2(CO)12] 1 with functionally substituted alkyne ligands HC≡CR 2 (R = FeCp2) and 3 (R = 2-OH-C6H4COOCH2), respectively in n-hexane at room temperature, two new cluster derivatives [Rh2Co2(CO)6(-CO)4(4, 2-HC≡CR)] 4 (R = FeCp2) and 5 (R = 2-OH-C6H4COOCH2) were obtained respectively. The alkyne was inserted into the CoCo bond of cluster 1 to give two butterfly clusters. Cluster 4 has been determined by single-crystal X-ray diffraction. Crystallographic data: C22H10Co2FeO10Rh2, Mr = 813.83, orthorhombic, space group P212121, a = 11.5318(7), b = 12.6572(7), c = 17.018(1) ? V = 2483.9(3) 3, Z = 4, Dc = 2.176 g/cm3, F(000) = 1568, = 3.233 mm-1, the final R = 0.0366 and wR = 0.0899 for 5367 observed reflections with I > 2(I). The two clusters have also been characterized by elemental analysis, IR and 1H-NMR spectroscopy.
The optical active alkyne-bridged Mo-Co heterometal complexes are synthesized by the chiral phase transfer catalyst (N-benzylcinchorin chloride) induced metal exchange reaction. The complex is used as catalyst to promote the asymmetric addition of diethylzinc to benzaldehyde. The ee value of the product alcohol is 5.7%, which illustrates the asymmetric induction of the tetrahedral framework chirality in asymmetric catalysis reaction for the first time.
The new chiral cluster [NiRuMo(CO)5(m3-S)(h5-C5H5)(h5-C5H4COCH3)] 3 was synthesized by the reaction of precursor [CoRuMo(CO)8(m3-S)(h5-C5H4COCH3)] 1 with NiCp2 2 in refluxing THF. It was characterized by C/H elemental analysis, IR and 1H NMR. Molecular structure of cluster 3 was determined by single-crystal X-ray analyses. Crystal data: triclinic, space group P with the following crystallographic parameters: a = 7.9606(8), b = 8.5604(9), c = 14.779(2) , a = 93.908(2), b = 105.057(2), g = 101.463(2)? C17H12O6MoNiRuS, Mr = 600.05, Z = 2, V = 945.5(2) 3, Dc = 2.108 g/cm3, m = 2.568 mm-1, (2q )max ≤ 56.48, F(000) = 584,the final R = 0.0380 and wR = 0.0674 for 2995 observed reflections with I > 2.00s(I).
