Chiroptical properties of pyranoid glycols in the presence of [Mo2(O[2CCH3)4]

✍ Scribed by András Lipták; Jadwiga Frelek; Günther Snatzke; Iontscho Vlahov

• Publisher: Elsevier Science
• Year: 1987
• Tongue: English
• Weight: 651 KB
• Volume: 164
• Category: Article
• ISSN: 0008-6215
• DOI: 10.1016/0008-6215(87)80127-1

✦ Synopsis

ABSTRAm

Bidentate complexes between [Mo,(O,CCH,)J and suitable diols from the sugar series show Cotton effects around 500 to 450 (CD band I), 400 (II), 350 (III), and 300 nm (IV), and additional effects at still shorter wavelengths. The sign of Cotton effect IV is identical with the sign of the torsional angle HO-C-C-OH for vie-diols. With this rule the absolute configurations of open-chain vie-diols of the fhreo-configuration and of vicinal primary-secondary diols can be determined with small amounts of substance; for the application of the rule the torsional angle(s) HO-C-C-C should be fixed at 180". Cotton effect III is only strong for vie-diols having a pyranose ring if no axial RO group is adjacent to the glycol moiety. Complexes of diols of pyranose structure carrying free hydroxyls at C-4 and C-6 show much smaller AE values.