Determination of the absolute structure of the chiral crystal consisting of achiral dibutylhydroxytoluene and asymmetric autocatalysis triggered by this chiral crystal

Abstract

Absolute structure is determined of chiral crystal composed of achiral dibutylhydroxytoluene (BHT, 2,6-di-tert-butyl-p-cresol) by single crystal X-ray diffraction and circular dichroism. Left-handed (M-) crystals exhibited a positive Cotton effect at a wavelength of approximately 288nm observed using KBr disk [CD(+)288KBr]. In contrast, right-handed (P-) crystals exhibited a negative Cotton effect at the same wavelength [CD(−)288KBr]. Asymmetric autocatalysis is triggered by the chiral crystals of achiral BHT, i.e., M-(+)-BHT afforded (S)-pyrimidyl alkanol and P-(−)-BHT afforded (R)-pyrimidyl alkanol.