111269-66-0Relevant articles and documents
Asymmetric 1,2-Perfluoroalkyl Migration: Easy Access to Enantioenriched α-Hydroxy-α-perfluoroalkyl Esters
Wang, Pan,Feng, Liang-Wen,Wang, Lijia,Li, Jun-Fang,Liao, Saihu,Tang, Yong
supporting information, p. 4626 - 4629 (2015/04/27)
This study has led to the development of a novel, highly efficient, 1,2-perfluoro-alkyl/-aryl migration process in reactions of hydrate of 1-perfluoro-alkyl/-aryl-1,2-diketones with alcohols, which are promoted by a Zn(II)/bisoxazoline and form α-perfluoro-alkyl/-aryl-substituted α-hydroxy esters. With (-)-8-phenylmenthol as the alcohol, the corresponding menthol esters are generated in high yields with excellent levels of diastereoselectivity. The mechanistic studies show that the benzilic ester-type rearrangement reaction takes place via an unusual 1,2-migration of electron-deficient trifluoromethyl group rather than the phenyl group. The overall process serves as a novel, efficient, and simple approach for the synthesis of highly enantioenriched, biologically relevant α-hydroxy-α-perfluoroalkyl carboxylic acid derivatives.
Electrophilic Substitution at Azomethine Carbon Atoms. Reaction of Aromatic Aldehyde Hydrazones with Trifluoroacetic Anhydride
Kamitori, Yasuhiro,Hojo, Masaru,Masuda, Ryoichi,Fujitani, Toshihiko,Ohara, Seiji,Yokoyama, Tetsuya
, p. 129 - 135 (2007/10/02)
Reaction of dimethylhydrazones of aromatic aldehydes with trifluoroacetic anhydride at room temperature affords high yields of products bearing trifluoroacetyl groups.These electrophilic substitution reactions generally occur on the azomethine carbon, although competitive N-acylation is observed in highly electron-rich systems.Use of diisopropylhydrazones suppressed this N-acylation completely, leading to high yields of C-acylated products.The trifluoroacetyl hydrazones can be cyclized thermally to imidazole and oxadiazine derivatives and can be converted into 1-trifluoromethyl 1,2-diketones by acid hydrolysis.
