甲肟基团已成为多种 C-H 官能化的多功能导向基团。尽管甲肟作为一种强大的功能手柄很重要,但通常需要将甲肟转化为母酮,但通常需要苛刻且官能团不耐受的反应条件。因此,甲肟的应用及其随后在后期转化为相应的酮可能会出现问题。在这里,我们提出了一组替代条件,以使用光激发硝基芳烃实现甲肟到母酮的温和且官能团耐受的转化。该方法的实用性体现在其在头孢内酯 D 的全合成中的应用。此外,还提供了通过同位素标记研究以及反应副产物分析获得的这种转化的机制见解。
Rh(III)-Catalyzed Addition of Alkenyl C–H Bond to Isocyanates and Intramolecular Cyclization: Direct Synthesis 5-Ylidenepyrrol-2(5<i>H</i>)-ones
作者:Wei Hou、Bing Zhou、Yaxi Yang、Huijin Feng、Yuanchao Li
DOI:10.1021/ol4003674
日期:2013.4.19
The rhodium-catalyzed addition of an alkenyl C–H bond to isocyanates via sp2 C–H bond activation followed by an intramolecular cyclization is described. This atom-economic and catalytic reaction affords a simple and straightforward access to biologically relevant 5-ylidene pyrrol-2(5H)-ones and can be carried out under mild and neutral conditions in the absence of any additives and environmentally
A nickel-catalyzed cycloaddition of α,β-unsaturated oximes with alkynes to afford 2,3,4,6-tetrasubstituted pyridine derivatives has been developed. The reaction involves oxidative addition of the N...
已开发出镍催化的 α,β-不饱和肟与炔烃的环加成反应,得到 2,3,4,6-四取代的吡啶衍生物。该反应涉及 N 的氧化加成...