Formal (3+3) cycloaddition of silyl enol ethers catalyzed by trifric imide: domino Michael addition-claisen condensation accompanied with isomerization of silyl enol ethers.
نویسندگان
چکیده
We describe here a Tf₂NH-catalyzed formal (3+3) cycloaddition of silyl enol ethers with acrylates as a new domino reaction. In the domino sequence, the catalyst activates Michael addition, deprotonation of the resulting silyloxonium cation and intramolecular Claisen condensation. It was found that reaction modes significantly depend on the reaction temperature. We also examined the mechanistic detail of the reaction by ¹H-NMR experiment.
منابع مشابه
Facile isomerization of silyl enol ethers catalyzed by triflic imide and its application to one-pot isomerization–(2 + 2) cycloaddition
A triflic imide (Tf(2)NH) catalyzed isomerization of kinetically favourable silyl enol ethers into thermodynamically stable ones was developed. We also demonstrated a one-pot catalytic reaction consisting of (2 + 2) cycloaddition and isomerization. In the reaction sequence, Tf(2)NH catalyzes both of the reactions.
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ورودعنوان ژورنال:
- Chemical & pharmaceutical bulletin
دوره 59 9 شماره
صفحات -
تاریخ انتشار 2011