Studies On The Application Of Alpha-Fluorocarbonyl Compounds In The Construction Of Chiral Carbon-Fluorine Bonds

In the paper,the application ofα-fluorocarbonyl compounds as fluorinated blocks in the construction of chiral C(sp~3)-F bonds are introduced.The high stereoselective Mannich reaction ofα-fluoroalkyl esters,α-fluoroaryl esters,α-alkenyl fluoroacetates with chiral tert-butyl sulfoximides has been developed.And,a concise and highly effecient synthesis method of alpha-fluoro-quaternary carbon-chiral neutralβ-amino acid esters is developed.We find that the stereochemistry of the resulting products has a clear relationship with the structural properties of the fluorinated substrate and different reaction transition states have been proposed for the three fluorinated substrates.Fluoroalkylation ofα-fluoroketones(especially chain strongα-fluorinated ketones and fluoromethyl ketones)with N-(tert-butylsulfinyl)imines has been achieved with high diastereoselectivity.Theα-fluoro-β-aminoketones containing fluorinated quaternary carbon chiral centers were obtained in good yields and high diastereoselectivities.Further synthetic applications indicate that the fluorinatedα-carbon centers are robust under mild acidic or basic conditions.The approch can synthesize fluorochemicals with various fabric and containing stereo C-F structural units and provide efficient synthetic tools for the synthesis of related fluoro-active molecules.