Indium-Mediated -Allylation, -Prop
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- 作者：Kooyeon Lee ; Hyunseok Kim ; Tomoya Miura ; Koichi Kiyota ; Hiroyuki Kusama ; Sunggak Kim ; Nobuharu Iwasawa ; and Phil Ho Lee
- 刊名：Journal of the American Chemical Society
- 出版年：2003
- 出版时间：August 13, 2003
- 年：2003
- 卷：125
- 期：32
- 页码：9682 - 9688
- 全文大小：139K
- 年卷期：v.125,no.32(August 13, 2003)
- ISSN：1520-5126
文摘
3-tert-Butyldimethylsilyloxyalk-2-enylsulfonium salts, generated in situ from the reaction of 
,
-enones with dimethyl sulfide in the presence of TBSOTf, underwent a novel nucleophilic substitution withallylindiums to give silyl enol ethers of 
,
-alkenyl ketones in good yields, which correspond to formal Michaeladdition products. In a similar manner, 1,4-propargylation of propargylindiums onto the sulfonium saltsproduced the corresponding silyl enol ethers of ,-alkynyl ketones in good yields. Organoindium reagentsderived from 
-substituted propargyl bromide and indium afforded the corresponding silyl enol ethers of-allenyl ketones in good yields. The reaction proceeds via an addition-substitution mechanism involvingthe formation of allylic sulfonium salts. The presence of the intermediate sulfonium salt was confirmed byobservation of the low-temperature 1H NMR spectra.
,-enones with dimethyl sulfide in the presence of TBSOTf, underwent a novel nucleophilic substitution withallylindiums to give silyl enol ethers of ,-alkenyl ketones in good yields, which correspond to formal Michaeladdition products. In a similar manner, 1,4-propargylation of propargylindiums onto the sulfonium saltsproduced the corresponding silyl enol ethers of ,-alkynyl ketones in good yields. Organoindium reagentsderived from -substituted propargyl bromide and indium afforded the corresponding silyl enol ethers of-allenyl ketones in good yields. The reaction proceeds via an addition-substitution mechanism involvingthe formation of allylic sulfonium salts. The presence of the intermediate sulfonium salt was confirmed byobservation of the low-temperature 1H NMR spectra.