| Summary: | 博士 === 國立臺灣大學 === 化學學系 === 84 === In thisreasearch, We studied the radical addition to carbonyl
compounds. It was divided into four parts. In the first part,
the intramolecular free radical addition to acylsilane followed
by radical Brook rearrangement was discussed. In order to find
the scope and limitations of this type of reactions, we have
al- so ivestigated the steric effects of silyl groups, the
influence of different carbon chain length connecting the
radical and acy- lsilane, and the use of different types of
radicals. In the second part, the focus was to expand the
utility of the radical reactions mentioned above. The omega-
bromo-omega-tribu- tylstannyl acylsilanes or omega-xanthate-
omega-tributylstannyl acylsilanes were treated with catalytic
amount of tributyltin hydride. Regiospecific enol silyl ethers
were obtained in good yields. This process involoves the
generation of a terminal alpha-stannyl radical followed by
1,5-exo-cyclization and radic- al Brook rearrangement to give a
carboradical. A facile beta- scission then occurs to obtain an
enol silyl ether, and regener- ated tributyltin radical to
continue radical reactions.
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