Naphthalene derivatives and method for preparation thereof

摘要

A naphthalene derivative of the formula: <IMAGE> wherein R1 is hydrogen and R2 is lower alkyl or phenyl-lower alkyl; or R1 and R2 are combined together to form lower alkylene; X is halogen; and the absolute configuration at the asymmetric carbon atom shown by the asterisk is either (S)- or (R)-configuration, and a method of preparation thereof are disclosed. Said naphthalene derivative is useful as a chiral reagent for determining the optical purity of an optically active compound containing within its molecule at least one functional group selected from hydroxy, amino and imino groups.