A Greek cross dodecaphenylene: sparteine-mediated asymmetric synthesis of chiral D2-symmetric π-conjugated tetra-o-phenylenes
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منابع مشابه
A Greek cross dodecaphenylene: sparteine- mediated asymmetric synthesis of chiralD2- symmetric π-conjugated tetra-o-phenylenes
The asymmetric synthesis of a chiral, nonracemic π-conjugated system with D2 point group of symmetry, dodecaphenylene 4 is described. In the key step, (−)-sparteineand Cu(II)-mediated oxidation of 2,2′-dilithio-1,1′-biaryls in ether gives the corresponding dimers, tetra-o-phenylenes, in 80% isolated yields and 50–60% ee’s. X-Ray crystallography confi rms the structure of rac-4 and its molecular...
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ژورنال
عنوان ژورنال: Tetrahedron
سال: 2001
ISSN: 0040-4020
DOI: 10.1016/s0040-4020(01)00241-1