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|Section2= |Section3= }} Pirkle's alcohol is an off-white, crystalline solid that is stable at room temperature when protected from light and oxygen. This chiral molecule is typically used, in nonracemic form, as a chiral shift reagent in nuclear magnetic resonance spectroscopy, in order to simultaneously determine absolute configuration and enantiomeric purity of other chiral molecules. The molecule is named after William H. Pirkle, Professor of Chemistry at the University of Illinois whose group reported its synthesis and its application as a chiral shift reagent. ==Synthesis== Pirkle’s alcohol is synthesized by trifluoroacetylation of anthracene, to yield trifluoromethyl 9-anthryl ketone. Trifluoromethyl 9-anthryl ketone may be reduced with a chiral hydride reagent prepared from lithium aluminium hydride and (4S,5S)-(–)-2-ethyl-4-hydroxymethyl-5-phenyl-2-oxazoline to generate Pirkle’s alcohol with R absolute configuration. Alternatively, trifluoromethyl 9-anthryl ketone may be reduced with sodium borohydride to generate racemic Pirkle’s alcohol. The enantiomers are then derivatized to diastereomeric carbamates using enantioenriched 1-(1-Naphthyl)ethyl isocyanate (also developed by Pirkle). These diastereomers may be separated by column chromatography and hydrolyzed to obtain each enantiomer of Pirkle’s alcohol in enantiopure form. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Pirkle's alcohol」の詳細全文を読む スポンサード リンク
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