Fraunhoffer Kenneth J, Narayanasamy Prabagaran, Sirois Lauren E, White M Christina
Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois 61801, USA.
J Am Chem Soc. 2006 Jul 19;128(28):9032-3. doi: 10.1021/ja063096r.
A novel Pd/sulfoxide-catalyzed macrolactonization reaction of linear omega-alkenoic acids is reported that proceeds via serial ligand-catalyzed allylic C-H oxidation. The scope of this macrolactonization appears to be very broad. Aryl, alkyl, and (Z)-alpha,beta-unsaturated acids are all competent nucleophiles for this reaction, with the latter undergoing macrolactonization with no olefin isomerization. High functional group compatibility is observed that includes biologically and medicinally relevant functionality such as ortho-substituted salicylate esters, bis(indoyl)maleimides, and peptides. Evidence is provided to support the hypothesis that macrolactonization proceeds via inner-sphere functionalization from a templated pi-allylPd carboxylate intermediate.
报道了一种新型的钯/亚砜催化的线性ω-链烯酸大环内酯化反应，该反应通过一系列配体催化的烯丙基C-H氧化进行。这种大环内酯化反应的适用范围似乎非常广泛。芳基、烷基和（Z）-α，β-不饱和酸都是该反应的有效亲核试剂，后者进行大环内酯化反应时没有烯烃异构化。观察到该反应具有高官能团兼容性，包括具有生物学和医学相关性的官能团，如邻位取代的水杨酸酯、双（吲哚基）马来酰亚胺和肽。有证据支持大环内酯化反应通过模板化的π-烯丙基钯羧酸盐中间体的内球官能化进行的假设。
