Highly Efficient Approach to 4-Ethoxy-5,6-dihydro-6,6-disubstituted Pyran-2-ones using a Combinational Lewis Acid-Base System
作者:Jie Liu、Xing Li、Jun Wang、Xiaoming Feng
DOI:10.1002/adsc.200505383
日期:2006.5
The first efficientapproach to 5,6-dihydro-6,6-disubstituted pyran-2-ones was successfully achieved from the reaction between commercially available ethyl 3-ethoxybut-2-enoate and ketones in the presence of BF3⋅Et2O, InBr3 and LDA. BF3⋅Et2O and InBr3 were employed as the Lewis acid to activate the ketone and LDA was employed as the Lewis base to activate ethyl 3-ethoxybut-2-enoate. Aromatic, aliphatic