Iridium-Catalysed ortho-Directed Deuterium Labelling of Aromatic Esters—An Experimental and Theoretical Study on Directing Group Chemoselectivity
作者:Jennifer Devlin、William. Kerr、David Lindsay、Timothy McCabe、Marc Reid、Tell Tuttle
DOI:10.3390/molecules200711676
日期:——
Herein we report a combined experimental and theoretical study on the deuterium labelling of benzoate ester derivatives, utilizing our developed iridium N-heterocyclic carbene/phosphine catalysts. A range of benzoate esters were screened, including derivatives with electron-donating and -withdrawing groups in the para- position. The substrate scope, in terms of the alkoxy group, was studied and the nature of the catalyst counter-ion was shown to have a profound effect on the efficiency of isotope exchange. Finally, the observed chemoselectivity was rationalized by rate studies and theoretical calculations, and this insight was applied to the selective labelling of benzoate esters bearing a second directing group.
本文报道了一项关于苯甲酸酯衍生物氘标记的实验与理论结合研究,利用了我们开发的铱N-杂环卡宾/膦催化剂。筛选了一系列苯甲酸酯,包括在对位具有给电子和吸电子基团的衍生物。研究了烷氧基团的底物范围,并发现催化剂反离子的性质对同位素交换效率有深远影响。最后,通过速率研究与理论计算合理化了观察到的化学选择性,并将这一见解应用于带有第二导向基团的苯甲酸酯的选择性标记。