The abnormal behavior of an atropisomer: 3,3'-dibromo-1,1'-difluoro-2,2'-binaphthyl reacting with alkyllithium compounds

1-Fluoro-2-(triethylsilyl)naphthalene and other 1-fluoronaphthalene derivs. bearing a metalation-resistant substituent at the 2-position proved to be totally inert toward base attack. 3-Bromo-1-fluoronaphthalene, readily prepd. from a 2-bromo isomer by deprotonation-triggered heavy halogen migration, was converted into 3,3'-dibromo-1,1'-difluoro-2,2'-binaphthyl (I) by consecutive treatment with lithium diisopropylamide, copper(II) bromide and nitrobenzene. The dilithiated intermediate generated from the atropisomer I by treatment with 2 equiv. of butyllithium reacted with a variety of electrophiles to afford products such as, diacid or bis(phosphane) derivs. . in high yields. The latter compd. was also obtained in a straightforward manner from (4-fluoro-2-naphthyl)diphenylphosphine oxide. Unexpectedly, neither the 3,3'-dibromobinaphthyl I nor its 3,3'-diiodo analog were amenable to a unilateral but only to a double-sided halogen/metal permutation. [on SciFinder (R)]