The synthesis of this class of compounds relies on the lithiation of racemic 2,2'-dibromo-1,1'-binaphthyl with t-BuLi followed by addition of Ph 2 PCl.
Purification Methods
Purify the binaphthyl by chromatography through a silica gel column (70-230mesh) using hexane as eluent. It gives pale yellow crystals from EtOH with m 187.3-187.9o. The R-(+)-enantiomer [86688-08-6] crystallises from hexane with m 157-157.5o and [] D +32.9o (c 1, pyridine) [Brown et al. J Org Chem 50 4345 1985]. [Okamoto et al. J Am Chem Soc 103 69711981, Beilstein 5 III 2465.]
