Fluorine and trifluoromethyl substituted anilines: site selective metalation and electrophilic substitution
When treated with tert-butyllithium in THF at -50 Deg, N-BOC (tert-butoxycarbonyl) protected fluoroanilines and trifluoromethylanilines, e.g., o-, m-, or p-F3CC6H4NHCO2CMe3, undergo metalation at the position adjacent to that carrying the nitrogen. If, however, the nitrogen carries two alkyl or trimethylsilyl groups as substituents and highly polar metalating reagents such as butyllithium activated by N,N,N',N",N"-pentamethyldiethylenetriamine (PMDTA) or potassium tert-butoxide are employed, the fluoroaniline derivs. are preferentially deprotonated next to the halogen atom. [on SciFinder (R)]
Keywords: Neighboring group participation; Regiochemistry; Substituent effect (in lithiation of fluoro- and trifluoromethyl-substituted anilines); Lithiation (regioselective ; of fluoro- and trifluoromethyl-substituted anilines) ; lithiation regioselective fluoroaniline; substituent effect lithiation fluoroaniline
Benzene, Its Derivatives, and Condensed Benzenoid Compounds
Inst. Chim. Org.,Univ. Lausanne,Lausanne,Switz.
written in English.
403-46-3; 60144-53-8; 81740-18-3; 98968-72-0; 109134-07-8; 141940-36-5; 141940-37-6; 141940-38-7; 141940-39-8 Role: RCT (Reactant), RACT (Reactant or reagent) (lithiation of, regioselectivity in); 446-31-1P; 141940-27-4P; 141940-28-5P; 141940-29-6P; 141940-30-9P; 141940-31-0P; 141940-32-1P; 141940-33-2P; 141940-34-3P; 141940-35-4P Role: SPN (Synthetic preparation), PREP (Preparation) (prepn. of)
Record created on 2006-03-03, modified on 2016-08-08