標題: | PHOTOCYCLOADDITION OF FUMARONITRILE TO ADAMANTAN-2-ONES AND MODIFICATION OF FACE SELECTIVITY BY INCLUSION IN BETA-CYCLODEXTRIN AND ITS DERIVATIVES |
作者: | CHUNG, WS WANG, NJ LIU, YD LEU, YJ CHIANG, MY 應用化學系 Department of Applied Chemistry |
公開日期: | 1-二月-1995 |
摘要: | The face selectivity in 5-substituted-adamantan-2-ones (1-Xs) can be dramatically reversed by means of inclusion into beta-cyclodextrin (beta-CD) and its heptakis(6-O-hydroxypropyl), heptakis(6-O-acetyl), heptakis(2,3,6-tri-O-methyl) and heptakis(2,3,6-tri-O-acetyl) derivatives. The 5-substituents varied from fluoro, chloro, bromo, phenyl to trimethylsilyl, and face selectivities of the oxetane formation have been found to vary with the sizes of 5-substituents and cavities of beta-CDs. A 98:2 face selectivity was achieved when 1-SiMe(3) was used as a probe. The effect observed is interpreted by assuming that the carbonyl pi-face syn to the bulky 5-substituent is partially locked by the torus of the host due to complexation of 1-X and CD. Information obtained from H-1 NMR titration and X-ray powder diffraction study on the inclusion complex is consistent with the above explanation. X-ray single-crystal structure was used to determine the oxetane structure of anti-2-SiMe(3). |
URI: | http://dx.doi.org/10.1039/p29950000307 http://hdl.handle.net/11536/2097 |
ISSN: | 0300-9580 |
DOI: | 10.1039/p29950000307 |
期刊: | JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2 |
Volume: | |
Issue: | 2 |
起始頁: | 307 |
結束頁: | 313 |
顯示於類別: | 期刊論文 |