6-Chloro-2,4-dinitrophenylhydrazine as a useful crystalline agent for the determination of absolute configuration
作者:Yasushi Kawai、Motoko Hayashi、Norihiro Tokitoh
DOI:10.1016/s0040-4039(01)02159-1
日期:2002.1
For the determination of absoluteconfiguration, we designed and synthesized some hydrazines as crystalline auxiliaries having a heavy atom, and found that 6-chloro-2,4-dinitrophenylhydrazine is a useful crystalline agent for chiral carbonyl compounds. The absoluteconfigurations of chiral hydrazones prepared from the hydrazine and chiral ketones were determined by X-ray crystallographic analysis.
Chlorodinitrophenylhydrazine, a useful crystalline agent for absolute configuration determination of various chiral ketones
作者:Yasushi Kawai、Motoko Hayashi、Norihiro Tokitoh
DOI:10.1016/j.tet.2005.03.037
日期:2005.5
For the determination of absoluteconfiguration of various chiral ketones, we examined some hydrazines having a heavy atom as crystalline auxiliaries, and found that 2-chloro-4,6-dinitrophenylhydrazine is a useful crystalline agent for carbonyl compounds. Chiral hydrazones prepared from the hydrazine and various chiral ketones gave suitable single crystals for X-ray crystallographic analysis. The absolute
Asymmetric synthesis of α-chiral ketones by the reduction of enones with baker's yeast
作者:Yasushi Kawai、Motoko Hayashi、Norihiro Tokitoh
DOI:10.1016/s0957-4166(01)00537-7
日期:2001.11
asymmetric reduction of α,β-unsaturatedketones (enones) having a pyridyl ring affords the corresponding optically active α-substituted ketones (α-chiral ketones) with excellent stereoselectivity. The position of the heteroatom, as well as the bulk of the α-substituent, plays an important role in governing the stereoselectivity in the reduction of a carboncarbon doublebond.