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bon-oxygen double bond. The carbonyl ligands possess carbonoxygen triple bonds with an average value of 1.16 Á.Acknowledgment. Financial support of this research by the National Science Foundation (Grant CHE 88-17873) and the Robert A. Welch Foundation is greatly appreciated.

The sense of the induction of the adducts in Table I (entries 8-10) could be established by correlation13 with (J?)-3-aminobutan-l-ol.314 The results confirm that amine addition does, in fact, take place preferentially on the re face of the crotonate unit, in agreement with related work.1115 This new enantioselective route to /3-amino esters is incontestably one of the most efficient asymmetric carbon-nitrogen bond-forming reactions known to date; furthermore the new 8arylmenthols that we have developed during the course of this work will undoubtedly prove to be powerful and general chiral auxiliaries in other enantioselective processes.

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We have used X-ray absorption spectroscopy to determine the electronic and geometric structure of the copper active site in methanol synthesis catalysts. Compared to the edge and FT of the MAFS data of CuO, the data suggest that most of the Cu(I1) in the calcined form does not have the same ligation as in the CuO lattice and more importantly that some of the Cu is dissolved in the ZnO lattice. For the reduced sample, the edge shifts to laver energy after reduction, indicating the presence of either Cu(1) or Cu(0). The EXAFS data analyses of reduced catalysts show the presence of copper clusters. Reaction with H S is shown to decompose the Cu clusters in the reduced catalyst and the level 8f Cu cluster decomposition increases with further reaction at higher temperature and longer time period.