Axially chiral 3, 3'-bi (1-benzothiophene)-2, 2'-dicarboxylic acid and its derivatives

M Mézlová, H Petříčková, P Maloň…

Index: Mezlova, Marie; Petrickova, Hana; Malon, Petr; Kozmik, Vaclav; Svoboda, Jiri Collection of Czechoslovak Chemical Communications, 2003 , vol. 68, # 5 p. 1020 - 1038

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Citation Number: 6

Abstract

Abstract Ullmann dimerization of substituted methyl 3-X-1-benzothiophene-2-carboxylates 1- 7 (X= Cl, Br) gave rise to the corresponding dimeric 3, 3'-bi (1-benzothiophene) esters 8-13. Resolution of the title acid 20 by fractional crystallization of its mono-and bisquininium salt afforded pure (R)-and (S)-enantiomers, the optical purity and absolute configuration of which was confirmed by CD spectrometry and by X-ray crystallography. Ullmann dimerization of ...