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The use of suitable predetermined building blocks has assumed an increasing relevance in recent times in the crystal engineering of coordination frameworks [1] that have potential interest as zeolite-like materials. [2] In this regard, much d) N. ] Racemic 1 was prepared by the lithiation of 2-alkynyl-5bromopyrimidine followed by treatment with 2-methylpropanal.[8] Preparation of (S)-1 with ca. 0.00005 % ee. Pyrimidyl alkanol (S)-1 (1.5 mg, > 99.5 % ee) was dissolved in ethyl acetate (or benzene) to make a standardized solution of (S)-1 (3.2 î 10 À6 mol L À1 ). The solution (50 mL) was added to a solution of racemic 1 (75.1 mg) in ethyl acetate (or benzene). Then, a part of the solution was transferred to another flask, and the removal of solvent gave (S)-1 with ca. 0.00005 % ee (9.9 mg). Dissolution of the whole (S)-1 in 4.3 mL of cumene produced a 9.9 î 10 À3 m solution of (S)-1 with ca. 0.00005 % ee. [9] a) K. Soai, S. Niwa, Chem. Rev. 1992, 92, 833 ± 856; b) L. Pu, H.-B. Yu, Chem. Rev. 2001, 101, 757 ± 824. [10] After our experiments were completed, Singleton and Vo reported asymmetric autocatalysis using (R)-(2-methylpyrimidyl)alkanol [5b] with the order of 10 À5 % ee [a) D. A. Singleton, L. K. Vo, J. Am. Chem. Soc. 2002, 124, 10 010 ± 10 011]. However, they used only the catalyst with the R configuration. We believe that it is essentially important to examine the asymmetric autocatalysts of both configurations. The reasons are as follows:1) The chirality level of the catalyst on the order of 10 À5 % ee is Sato,

Au nanoparticles are known to be a good catalyst or an effective promoter for a wide range of catalytic reactions. Bimetallic Au-Pd nanoparticles supported on activated carbon were synthesized following a twostep procedure: immobilization of Au sol onto activated carbon followed by immobilization of Pd(0). The catalysts showed superior activities compared to monometallic Pd or Au nanoparticles on the same support. A series of catalysts with Au:Pd ratios varying from 9.5:0.5 to 2:8 were prepared. These catalysts were characterized by TEM, HRTEM, EDX, and X-ray mapping techniques to obtain morphological information, particle size distributions, crystalline structure, and distribution of the two metals. Correlating with the result from catalytic tests of selective oxidation of glycerol to glyceric acid, we found that the surface configuration of Pd monomers isolated by Au atoms has a substantial effect on activity and stability. The Au:Pd ratio on the surface of the particles is the key parameter and can be finely tuned to achieve optimal catalytic performance. The segregation or inhomogeneity of Pd weakens the synergistic effect of the bimetallic catalyst

Single phase bimetallic Au/Pd catalyst was prepared and characterised by TEM techniques. The high activity in the selective liquid phase oxidation of glycerol towards glycerate is unambiguously attributed to the synergistic effect of alloy.

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The influence of metal particle size of monometallic and bimetallic supported catalysts (Au, Pd, Au-Pd)/C was studied using as a model reaction the liquid phase oxidation of glycerol. By tuning the metal particle size from 2 to 16 nm a progressive decrease of activity and simultaneously an increase in the selectivity to sodium glycerate was observed. Moreover, the influence of the temperature was studied and it was found that by increasing the temperature, only with a large particle size the formed glycerate was retained and not over-oxidized to tartronate.