Catalysis with earth‐abundant transition metals is an option to help save our rare noble‐metal resources and is especially interesting when novel reactivity or selectivity patterns are observed. We report here on a novel reaction, namely the dehydrogenative alkylation or α‐olefination of alkyl‐substituted N‐heteroarenes with alcohols. Manganese complexes developed in our laboratory catalyze the reaction
pyridylboronic acids is realized under rhodiumcatalysis. Chemodivergent pyridylation products, including alkenylpyridines produced via the hydropyridylation pathway and cyclopenta[c]pyridines produced via the pyridylation/cyclization pathway, were selectively produced by fine-tuning the reaction conditions. A mechanistic study revealed that 1,4-rhodium migration to the pyridine ring was involved as the key step
炔烃与吡啶基硼酸的吡啶化反应是在铑催化下实现的。通过微调反应条件选择性地产生化学发散性吡啶化产物,包括通过氢化吡啶化途径产生的烯基吡啶和通过吡啶化/环化途径产生的环戊[ c ]吡啶。一项机理研究表明,1,4-铑迁移到吡啶环是化学发散合成的关键步骤。
Koenigs; Koehler; Blindow, Chemische Berichte, 1925, vol. 58, p. 938
作者:Koenigs、Koehler、Blindow
DOI:——
日期:——
MnO2 mediated sequential oxidation/olefination of alkyl-substituted heteroarenes with alcohols
ligand-free MnO2 mediated sequentialoxidation and olefination has been developed for the facile synthesis of a broad range of unsaturated N-heteroazaarenes from simple alkyl-substituted heteroarenes and alcohols. The procedure tolerates a series of functional groups, such as methoxyl, chloro, bromo, iodo, vinyl, phenolic and hetero groups, providing the olefination products in moderate to good yields