67665-45-6Relevant articles and documents
Synthesis of enantiomerically pure dissymmetric 2,2′-disubstituted 9,9′-spirobifluorenes
Thiemann, Frank,Piehler, Torsten,Haase, Detlev,Saak, Wolfgang,Luetzen, Arne
, p. 1991 - 2001 (2007/10/03)
Racemic dissymmetric 2,2′-dihydroxy-9,9′-spirobifluorene was prepared and resolved by clathrate formation with (R,R)-(+)-2,3-dimethoxy-N,N, N′,N′-tetracyclohexylsuccindiamide, giving rise to both enantiomers in very good yields. The absolute stereochemistry of the resolved material could be assigned by an X-ray structure analysis of single crystals of the clathrate. Enantiomerically pure diols could be transformed into the corresponding ditriflates, which were then used as starting materials in different cross-coupling procedures to provide a number of new enantiomerically pure spiro compounds bearing versatile functional groups suitable for further elaboration, as demonstrated by some examples. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.