BF₃·OEt₂: An Efficient Catalyst for Transesterification of β-Ketoesters

Abstract

A facile and selective transesterification of β-ketoesters using BF₃·OEt₂ as catalyst is described. The emphasis has been placed on the reaction of methyl acetoacetate with a series of alcohols of different structures, leading in all cases to good to excellent yields.

Keywords:

• β-Ketoesters
• Carroll rearrangement
• transesterification

ACKNOWLEDGMENTS

The work was supported by the Ministry of National Education (No. 203143), the National Natural Science Foundation of China (Nos. 20562010, 20962016), the special pre-inquest of State 973 (No. 2006CB708606), the Key Laboratory of Energy Resources and Engineering (Ningxia University), and the Province and Ministry of Education of China.

Notes

^a The molar ratio of methyl acetoacetate and n-butanol is 1:1.5.

^b Isolated yield.

^a All reactions were carried out with 15 mol% of BF₃·OEt₂ in refluxing toluene for the appropriate time.

^b Isolated yield. All products were characerized by their ¹H NMR, ¹³C NMR, or mass spectroscopic data.

^c No reaction.