Mechanistic Studies on alpha-Trifluoromethylation of Ketones via Silyl Enol Ethers and Its Application to Other Carbonyl Compounds

作者：Sato Kazuyuki; Yuki Takashi; Yamaguchi Ryoji; Hamano Tetsuya; Tarui Atsushi; Omote Masaaki; Kumadaki Itsumaro; Ando Akira^*

来源：Journal of Organic Chemistry, 2009, 74(10): 3815-3819.

DOI：10.1021/jo9004348

Synthesis of alpha-CF(3) carbonyl compounds has been recognized to be difficult up to now because the polarization of CF(3)(delta-)-I(delta ) is opposite to that of CH(3)(delta )-I(delta-), and this makes it difficult to introduce CF(3)( ) unit to enolates. We recently reported an effective alpha-trifluoromethylation of ketones by using Et(2)Zn with Rh catalyst, but the mechanism has not fully been cleared. Now, we carried out the detailed mechanistic studies and found the involvement of a highly reactive alkylrhodium complex which derived from Et(2)Zn and RhCl(PPh(3))(3) in this alpha-trifluoromethylation. Furthermore, this alpha-trifluoromethylation was applied to other types of carbonyl compounds in good yields.

• 出版日期2009-5-15