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Reactive ion etching of ferroelectric (Bi 4 m x La x )Ti 3 O 12 (BLT) thin films has been studied using C 2 F 6 and HBr etch gases in an inductively coupled plasma (ICP). BLT thin films with bismuth layered-perovskite structure were prepared by chemical solution deposition method. Etch rate and etch selectivity of BLT films were investigated for each gas. The etch rate of 700∼900 A were obtained for C 2 F 6 gas while the etch rate by HBr gas were in the range of 700∼1100 A under the etch conditions used in this study. The etch profiles and surface morphologies of BLT films etched by each gas were observed using field emission scanning electron microscopy (FESEM). HBr chemistry turned out to be more effective in obtaining high etch rate and clean etch profile than C 2 F 6 chemistry.

Asymmetric carbon-carbon bond-forming reaction is one of the most valuable processes for construction of enantiomerically enriched molecules. Considerable research has been done on Pd-catalyzed asymmetric allylic alkylation. In particular, the search of new chiral ligands is an important chapter in the area and remains an area of intense research. We have previously found that phosphinooxazolidines 1 bearing sp nitrogen donor are useful ligands in the asymmetric allylic alkylation. The oxazolidines obtainable by simple synthetic route seem to be potential ligands for the asymmetric catalysis. As part of our continuing interest in oxazolidines, we herein disclose the preparation of new chiral pyridinyloxazolidines and their application in asymmetric allylic alkylation. The oxazolidines 2-4 were obtained through condensation of commercially available 2-pyridinecarboxaldehyde and optically pure (S)-N-methylalaninol, (S)-N-methylvalinol and (1R,2S)-ephedrine in good yields of 80%, 84%, and 90% respectively. The reaction leads to the formation of new