Abstract: In this paper seven o-alkoxy phenols and their corresponding isotope lithium compounds of ⁷Li and ⁶Li have been Frepared through the selective monoalkylating reaction of pyroca-techol and alkylhalides by phase transter catalyst. Li-O absorption frequencies in theIR spectra were found in the range of 500?100cm^-1, which obeyed the tetrahedron rule ofinorganic lithium compounds. The isotope effect by ⁶Li and ⁷Li was also observed.The strong double peak in the range of 1400-1350cm^-1 presented in the IR spectra of o-alkoxy phenol parent compounds disappeared in the spectra of their correspounding lithiumcompounds demonstrating the deformation vibration of OH in the alcohols and phenols The lithium compounds gave two kinds of aggregate ion peaks in mass spectra namely [Li_nR_n]⁺ and [Li_nR_n-1]⁺.

Key words: O-Alkoxy phenols, Phase transfer reaction, Lithium compounds