Tocopherol synthesis: chromane cyclization and catalysis
    2.
    发明授权
    Tocopherol synthesis: chromane cyclization and catalysis 失效
    TOCOPHEROL合成:CHROMANE CYCLIZATION和CATALYSIS

    公开(公告)号:US5110955A

    公开(公告)日:1992-05-05

    申请号:US505873

    申请日:1990-04-05

    摘要: The invention relates to a process for the manufacture of vinylchromanes. This process is concerned with the manufacture of the compounds having the formula ##STR1## wherein R.sup.o is hydrogen or a cleavable protecting group, and comprises cyclizing a compound having the formula ##STR2## wherein R.sup.o is defined above and R.sup.1 is--CH.sub.2 --CH.sub.2 --C(W)(CH.sub.3)--CH.dbd.CH.sub.2 or--CH.sub.2 --CH.sub.2 C(CH.sub.3).dbd.CH--CH.sub.2 --Wwhere W is a leaving group,by means of a chiral transition metal-diphosphine complex.The compounds of formula I are useful intermediates, e.g. in the manufacture of (R,R,R)-.alpha.-tocopherol.

    摘要翻译: 本发明涉及一种制备乙烯基色满的方法。 该方法涉及具有式Ia的化合物的制备,其中Ro是氢或可裂解的保护基,并且包括使具有上式定义的具有式II的化合物环化,并且R 1是-CH 2 - CH2-C(W)(CH3)-CH = CH2或-CH2-CH2C(CH3)= CH-CH2-W其中W是离去基团,通过手性过渡金属 - 二膦配合物。 式I的化合物是有用的中间体,例如 在(R,R,R)-α-生育酚的制造中。