Rec-Butyllithium

Early attempts to metalate 1,1-difluoroethylene with -butyllithium in tetra-hydrofuran or diethyl ether were unsuccessful. Another example whereby the course of the reaction may be altered by substitution of rec-butyllithium in place of n-butyllithium is the metalation of 1,1 -difluoroethylene [60] (equation 26)... 

Dilithiation of n,f -unsaturated amides. Two laboratories2-3 have reported that either n-butyiiithium or rec-butyllithium in combination with TMEDA can dimctalatc a,/(-unsuturalcd secondary amides and that the second metalation occurs selectively at the /f-position even when the -/-position bears a proton. A similar preference has been noted in aromatic systems.4 This dimetalation has been... 

At the beginning a comprehensive study was made of solvents, particularly ether. When some theoretical consideration suggested the probable advantages of rec-butyllithium and of tert-butyllithium for reactions such as metalation, we established that such RLi compounds could be made... 

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