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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,

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