Rw. Baker et Mv. Sargent, ATROPISOMER-SELECTIVE 1,1'-BINAPHTHYL SYNTHESIS VIA CHIRALITY TRANSFER FROM SULFUR, Pure and applied chemistry, 66(10-11), 1994, pp. 2143-2150
1-(Alkyl- or aryl-sulfinyl)naphthalenes activated by electron-withdraw
ing substituents at the 2-position undergo substitution reactions on t
reatment with Grignard reagents. Evidence suggesting that this transfo
rmation proceeds through a ligand coupling reaction of sigma-sulfurane
s is discussed. The ligand coupling reaction of homochiral sulfoxides
with 1-naphthylmagnesium bromide furnishes atropisomeric 1,1'-binaphth
yls in 60-95% e.e.