申请人:Takasago International Corporation
公开号:US05155240A1
公开(公告)日:1992-10-13
A process for producing an optically active dihydropyran derivative represented by formula (1): ##STR1## wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 each represents a hydrogen atom, a lower alkyl group, a tri-lower alkylsilylmethyl group, a lower alkoxycarbonylamino group, or an --OR.sup.5 group, wherein R.sup.5 represents a lower alkyl group, a lower acyl group, a lower alkoxycarbonyl group, a di-lower alkylcarbamoyl group, or a tri-lower alkylsilyl group, or R.sup.1 and R.sup.2 are taken together to form a 5- to 7-membered cyclic hydrocarbon group or to form a condensed heterocyclic group with an oxygen atom, or R.sup.2 and R.sup.3 are taken together to form a 5- to 7-membered cyclic hydrocarbon group or to form a condensed heterocyclic group with an oxygen atom, provided that all of R.sup.1, R.sup.2, R.sup.3, and R.sup.4 do not represent hydrogen atoms at the same time; and R.sup.6 represents a lower alkyl group, which comprises reacting a diene compound represented by formula (2): ##STR2## wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 have the same meanings as defined above, with a glyoxylic acid ester represented by formula (3): ##STR3## wherein R.sup.6 has the same meaning as defined above, in the presence of a binaphthol-titanium complex represented by formula (4): ##STR4## wherein X represents a chlorine atom or a bromine atom, is disclosed.
一种生产光学活性二氢吡喃衍生物的方法,其化学式为(1):##STR1## 其中R.sup.1、R.sup.2、R.sup.3和R.sup.4分别表示氢原子、低级烷基、三低级烷基硅甲基基团、低级烷氧羰基氨基基团或--OR.sup.5基团,其中R.sup.5表示低级烷基、低级酰基、低级烷氧羰基基团、二低级烷基氨基基团或三低级烷基硅基基团,或R.sup.1和R.sup.2结合形成5-至7-成员环烃基团或与氧原子形成紧缩杂环基团,或R.sup.2和R.sup.3结合形成5-至7-成员环烃基团或与氧原子形成紧缩杂环基团,前提是所有R.sup.1、R.sup.2、R.sup.3和R.sup.4不同时表示氢原子;且R.sup.6表示低级烷基。该方法包括在存在双萘酚钛配合物(化学式(4))的情况下,将化学式(2)所表示的二烯化合物与化学式(3)所表示的甘酸酯反应,其中R.sup.1、R.sup.2、R.sup.3和R.sup.4的含义如上所定义,R.sup.6的含义如上所定义,X表示氯原子或溴原子。