Asymmetric Autocatalysis with Amplification of Chirality

Abstract

A review. Chiral 5-pyrimidyl alkanols are highly enantioselective asym. autocatalysts for the addn. of i-Pr2Zn to the corresponding aldehyde. Asym. autocatalysts with amplification of ee from extremely low (0.00005%) ee to > 99.5% ee was realized for the first time by consecutive asym. autocatalysis. The chirality of CPL was directly correlated with the chirality of the pyrimidyl alkanol with high ee by aymmetric photodegrdn. of the racemic pyrimidyl alkanol in combination with asym. autocatalysis. Chiral inorg. crystals such as quartz act as chira triggers and regulate the sense of the asym. autocatalysis. Chiral org. crystals composed of an achiral compd. such as hippuric acid act as the initial source of chirality for asym. autocatalysis to produce the nearly enantiomerically pure product. Highly sensitive chiral discrimination of amino acids with low ee is described. Direct examn. of extraterrestrial chirality was performed on meteorities by applying asym. autocatalysis as the chiral sensor. Spontaneous abs. asym. synthesis is described in the formation of enantiomerically enriched pyrimidyl alkanol from the reaction of pyrimidine-5-carbaldehyde and i-Pr2Zn without adding any chiral substance in combination with asym. autocatalysis. Asym. autocatalysis of a chiral pyrimidyl alkanol is the only possible method to discriminate a cryptochiral quaternary satd. hydrocarbon, whose chirality is not capable of detn. by any current method. The discrimination of chirality due to deuterium substitution is also accessible by the highly sensitive asym. autocatalysis. of a chiral pyrimidyl alkanol is the only possible method to discriminate a cryptochiral quaternary satd. hydrocarbon, whose chirality is not capable of detn. by any current method. The discrimination of chirality due to deuterium substitution is also accessible by the highly sensitive asym. autocatalysis. [on SciFinder(R)]