应用核磁共振波谱法来测定有机化合物的光学对映体含量是很有意义的。通常,它有三种方法:①应用手性溶剂,②被测对映体形成非对映异构体方法,③手性位移试剂。Pirkle等应用的手性溶剂方法,虽可推测绝对构型,但往往由于对映位化学位移差值较小,不易准确测定含量。一般应用最广的Mosher试剂(光学活性α-甲氧基α-三氟甲基苯乙酸,MTPA)形成非对映异构体的方法,仅局限于测定醇或胺类化合物,此法有时还需普通位移试剂配合使用。手性位移试剂则可直接测定对映体的光学纯度。 1970年Whitesides和Lewist首先合成了手性位移试剂三-(3-叔丁基羟基亚甲基-d-樟脑) It is significant to use NMR spectroscopy to determine the optical enantiomeric content of organic compounds. In general, it has three methods: ① the use of chiral solvents, ② enantiomers to be measured to form diastereomers, ③ chiral displacement reagents. Pirkle and other applications of the chiral solvent method, although the absolute configuration can be speculated, but often due to the smaller differences in chemical shift of the opposite position, difficult to accurately determine the content. The most commonly used method for the formation of diastereoisomers by the Mosher reagent (optically active alpha-methoxy alpha-trifluoromethylphenylacetic acid, MTPA) is limited to the determination of alcohols or amines only and sometimes Need to use ordinary displacement reagent. Chiral shift reagents can be directly measured optical purity of enantiomers. In 1970, Whitesides and Lewist first synthesized chiral shift reagent tris- (3-t-butylhydroxymethylene-d-camphor)