Eremophilane esters of Robinsonecio gerberifolius and their rearranged products. Study of the coupling constants 2JH, H, 3JH, H and 4JH, H

✍ Scribed by Amira Arciniegas; Ana-L. Pérez-Castorena; Gabriel Cuevas; Federico del Río-Portilla; Alfonso Romo de Vivar

• Book ID: 102524702
• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 112 KB
• Volume: 44
• Category: Article
• ISSN: 0749-1581
• DOI: 10.1002/mrc.1719

✦ Synopsis

Abstract

In the course of the basic hydrolysis of four eremophilane esters isolated from Robinsonecio gerberifolius, some rearrangements, eliminations, and additions occurred. Five compounds were obtained, three of them not previously described. Additionally, a new sesquiterpene was produced by autooxidation of compound 1. The ^1^H and ^13^C NMR spectra of these compounds were completely assigned by utilization of HMQC, HMBC, COSY, DEPT, and NOESY techniques. The long‐range coupling constants of the peroxide 10 are reported, and all its coupling constants ^2^J~H, H~, ^3^J~H, H~, and ^4^J~H, H~ are calculated at the B3LYP/6‐31G(d,p) level of theory. Their magnitude is explained in terms of electronic delocalization and the additivity of stereoelectronic effects. Copyright © 2005 John Wiley & Sons, Ltd.