Molecular Vibrations of Quinones. III. Preparation and Infrared Spectra (Solution and Vapor) of p-Benzoquinone-d1, p-Benzoquinone-2,5-d2, p-Benzoquinone-2,6-d2, p-Benzoquinone-18O2, and p-Benzoquinone-d4-18O2

Abstract

Three specifically deuterated quinones, p‐benzoquinone‐d₁, ‐2,5‐d₂, and ‐2,6‐d₂, have been prepared by a scheme involving (1) the formation of the dibenzyl ether of the appropriate bromohydroquinone, (2) reaction of this bromoether with n‐butyl lithium, (3) introduction of deuterium by solvolysis of the lithium derivative in D₂O, (4) cleavage of the ether with sodium in liquid ammonia, and (5) oxidation of the specifically deuterated hydroquinone by chromic oxide in buffered acetic acid. Infrared spectra have been obtained for the three compounds both in solution (4000–75 cm⁻¹) and in vapor phase (4000–300 cm⁻¹). The band contours of the vapor spectra are analyzed and discussed. In addition, p‐benzoquinone‐¹⁸O₂ and quinone‐d₄‐¹⁸O₂ have been prepared by exchange of quinone and quinone‐d₄ with H₂¹⁸O. Solution spectra (4000–300 cm⁻¹) are reported.