Intramolecular hydrogen bonding of o-hydroxyesters and related compounds evaluated by deuterium isotope effects on 13C chemical shifts and principal component analysis
作者:Poul Erik Hansen、Fadhil S. Kamounah、Saif Ullah
DOI:10.1016/j.molstruc.2007.06.012
日期:2007.11
ester carbons show unusual deuterium isotope effects. A principal component analysis based on bond lengths and distances around the hydrogenbond six-membered ring make it possible to predict isotope effects. The ratio n ΔC O(OD)/ 2 ΔC(OD) can be used to predict the extent of transmission via the hydrogenbond. Furthermore, deuterium isotope effects can be used to gauge possible tautomerism.
摘要 通过氘同位素对 13 C 化学位移 x ΔC(OD) 的影响,研究了邻羟基芳族酯、β-羟基酮酯、Meldrums 酸、其他邻羟基酯和一些邻羟基酸酐。尤其是酯碳显示出不寻常的氘同位素效应。基于氢键六元环周围的键长和距离的主成分分析可以预测同位素效应。比率 n ΔC O(OD)/ 2 ΔC(OD) 可用于预测通过氢键的传输程度。此外,氘同位素效应可用于衡量可能的互变异构现象。
Improved methods for the reductive alkylation of methoxybenzoic acids and esters: applications to the synthesis of bicyclic ketones
作者:Robert J. Hamilton、Lewis N. Mander、S.Paul Sethi
DOI:10.1016/s0040-4020(01)90577-0
日期:1986.1
employed to introduce the elements of a butanone or pentanone side-chain as a prelude to adding a fused six-membered ring, thereby completing the preparation of several analogues of the Wieland-Miescher ketone 4a in which the angular substituent was oxygenated.