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Determination of absolute configuration of axially chiral biaryls

✍ Scribed by Kuninobu Kabuto; Fujiko Yasuhara; Shozo Yamaguchi

Publisher
Elsevier Science
Year
1981
Tongue
French
Weight
273 KB
Volume
22
Category
Article
ISSN
0040-4039

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✦ Synopsis

Sutmnary: Absolute configurations of axially chiral biaryls with hydroxyl, amino, and carboxyl groups can be easily determined by pmr spectra using MTPA derivatives and shift reagents. Recently chiral biaryls have been successfully utilized in the field of asynetric synthesis*. For example, virtually complete enantioselectivity was found in the reduction of phenyl alkyl ketones with lithium aluminum hydride modified by 2,2'-dihydroxy-l,l'-binaphthy12c. The determination of absolute configuration of these biaryls have been performed by several methods; X-ray analysis3, chemical correlation3, chiroptical methods4, and Prelog's synthesis5 etc. Although recently developed NMR techniques6 make it possible to determine conconmiitantly absolute configuration and enantiomeric purity of compounds with centro-chirality,no

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