Résumé

Methoxy- and fluoro-substituted benzylamines can be metalated optionally at the position adjacent to the nitrogen bearing side chain or adjacent to the hetero substituent as a function of the acyl-type protective group. Thus, lithiation of 2-FC6H4CH2NHBOC with BuLi/KOCMe3 in THF followed by carboxylation with CO2 and acid workup afforded 50% 2,3-F(HO2C)C6H3CH2NHBOC, whereas lithiation of 2-FC6H4CH2NHCONMe2 with LiCMe3 in THF followed by carboxylation afforded 81% 2,6-F(HO2C)C6H3CH2NHCONMe2 regioselectively. [on SciFinder (R)]

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