申请人:——
公开号:US20030187296A1
公开(公告)日:2003-10-02
A method is provided for making an enantiomerically pure of the formula: in which R and R′ represent C1?C10 alkyl, C2?C10 alkenyl or C3?C10 cycloalkyl and the wedges signify (S)- or (R)-stereochemistry, the substituents in compound (II) being trans. Conjugate addition is carried out between an organometallic nucleophile that provides a group R as defined above and (R)-4-acetoxycyclopent-2-en-1-one, (S)-4-acetoxycyclopent-2-en-1-one or a similar compound in which acetoxy is replaced by another leaving group to give, e.g. in the case of the acetoxy compound, a trans 3,4-disubstituted addition product of formula III or IV; The acetyl group is eliminated from the addition product to give an (R)- or (S)-4-alkyl or 4-alkenyl cyclopent-2-en-1-one the compound of formula is then to be hydrogenated to give a cyclopentanone of formula (I) or conjugate addition of a second organometallic nucleophile that provides a group R′ as defined above to the compound of the above formula may be carried out to give a trans 3,4-disubstituted addition product of formula (II). One of the above compounds may be converted e.g. via an intermediate (XV)-(XVIII) (in which the substituents R and R′ and the wedges have the meanings indicated above) to a gabapentin analogue of one of the formulae shown below: in which the substituents R and R′ and the wedges also have the meanings indicated above.
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提供一种制备公式的对映纯物质的方法:其中R和R′代表C1-C10烷基、C2-C10烯基或C3-C10环烷基,楔形符号表示(S)-或(R)-立体化学,化合物(II)中的取代基为反式。在有机金属亲核试剂和(R)-4-乙酰氧基环戊-2-烯-1-酮、(S)-4-乙酰氧基环戊-2-烯-1-酮或类似化合物之间进行共轭加成,其中乙酰氧基被另一个离去基取代,例如在乙酰氧基化合物的情况下,得到公式III或IV的反式3,4-二取代加成产物;从加成产物中消除乙酰基,得到(R)-或(S)-4-烷基或4-烯基环戊-2-烯-1-酮,然后将该化合物氢化,得到公式(I)的环戊酮,或者对上述公式的化合物进行第二次有机金属亲核试剂的共轭加成,得到公式(II)的反式3,4-二取代加成产物。上述化合物之一可以通过中间体(XV)-(XVIII)(其中取代基R和R′以及楔形符号具有上述所示的含义)转化为下面所示的公式之一的加巴喷丁类似物:其中取代基R和R′以及楔形符号也具有上述所示的含义。