Enantioselective synthesis of α-methyl carboxylic acids using a DiTOX chiral auxiliary
作者:Philip C Bulman Page、Michael J McKenzie、Steven M Allin、Sukhbinder S Klair
DOI:10.1016/s0040-4020(97)00837-5
日期:1997.9
Five α-methyl carboxylic acids have been prepared with high e.e.s using 1,3-dithiane 1-oxide (DiTOX) units as the stereocontrolling elements and sources of chirality.
Chiral N,N-disubstituted amides may be readily synthesized by reacting an anhydride with l- or d-ephedrine.
通过使酸酐与1-或d-麻黄碱反应,可以容易地合成手性N,N-二取代的酰胺。
Enantioselective synthesis of (R)-(−)-2,6-dimethyl heptanoic acid: The first application of the DITOX asymmetric building block
作者:Philip C. Bulman Page、Steve M. Allin、Eric W. Collington、Robin A.E. Carr
DOI:10.1016/s0040-4039(00)77184-x
日期:1994.4
The 1,3-dithiane 1-oxide (DITOX) asymmetric building block/chiral auxiliary has been used to prepare (R)-(−)-2,6-dimethyl heptanoic acid (1), a simple derivative of citronellal, in two steps from (2).
Synthesis of chiral alkynes having 2H or halogen at the secondary or tertiary propargylic stereogenic center by hydrolysis and halogenolysis of optically active allenyltitaniums having axial chirality
作者:Duk Keun An、Sentaro Okamoto、Fumie Sato
DOI:10.1016/s0040-4039(98)00830-2
日期:1998.6
The hydrolysis and halogenolysis of opticallyactive allenyltitaniums, generated by the reaction of a reagent with opticallyactive propargyl alcohol derivatives, proceed in a regioselective way and with excellent degree of chiral transfer, thus opening up a highly efficient and practical route to chiral alkynes having 2H or Cl at the stereogenic propargylic center.
Optically active compound, antiferroelectric liquid crystal composition containing the same, process for producing the same and process for producing optically active carboxylic acid
申请人:Takasago International Corporation
公开号:EP0884309A1
公开(公告)日:1998-12-16
Disclosed is a novel optically active compound which exhibits no antiferroelectric liquid crystal phase but can be incorporated in an antiferroelectric liquid crystal having a high threshold voltage to reduce the threshold voltage thereof, an antiferroelectric liquid crystal composition containing the compound, a process for the reduction of the threshold voltage of an antiferroelectric liquid crystal composition, a process for producing the compound and a process for producing an optically active carboxylic acid as an intermediate.