✦ LIBER ✦

Substituent effects in aromatic proton nmr spectra. I. The role of inductive (or field) effect.

✍ Scribed by Yujiro Nomura; Yoshito Takeuchi

Publisher: Elsevier Science
Year: 1968
Tongue: French
Weight: 226 KB
Volume: 9
Category: Article
ISSN: 0040-4039
DOI: 10.1016/s0040-4039(00)75568-7

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✦ Synopsis

In an aromatic molecule, the chew6 ln the proton &amlcal ahlft wee aham to be proportional to the change ln n-electron charge denalty on the carbon l tac to which the hydrogen le bonded(l). For monoaubatltutod banxenea( III), howvar, thlr proportlonalltp l earae to hold only for the pare-proton shift. Ihua Wu and Dallay(2) rhowad that the linear correlation axiats between pare-proton mhlft and n-electron charge danalty calculated by tha XiUckal LO method. Schu~(3) proposed that the change in n-electron charge danalty of next-naaraat-neighbor carbon atcena

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