The first Fe-catalysed alkylation of 2-methyl and 4-methyl-azaarenes with a series of alkyl and hetero-aryl alcohols is reported (>39 examples and up to 95% yield). Multi-functionalisation of pyrazines and synthesis of anti-malarial drug (±) Angustureine significantly broaden the scope of this methodology. Preliminary mechanistic investigation, deuterium labeling and kinetic experiments including trapping
Iron-Catalyzed Direct Alkenylation of 2-Substituted Azaarenes with <i>N</i>-Sulfonyl Aldimines via C–H Bond Activation
作者:Bo Qian、Pan Xie、Yinjun Xie、Hanmin Huang
DOI:10.1021/ol200684b
日期:2011.5.20
A novel iron-catalyzed alkenylation of 2-substituted azaarenes through sp3 C–Hbondactivation has been developed. A favorable E2-elimination is proposed as a key step to cleavage of C–H and C–N bonds for the construction of a C═C bond in high stereoselectivity. This transformation represents an efficient way to synthesize 2-alkenylated azaarenes from simple starting materials.
Zinc-catalyzed chemoselective alkylation of α-keto amides with 2-alkylazaarenes
作者:Alagesan Muthukumar、Govindasamy Sekar
DOI:10.1039/c6ob02432g
日期:——
addition of 2-alkylazaarenes to α-keto amides to furnish azaarene incorporated α-hydroxy amides has been developed with a wide range of substrates in moderate to excellent yields, respectively. Chemoselectivealkylation of the keto functionality of the α-keto amides in the presence of simple ketones is the key advantage of this Zn-catalyzed transformation. This approach has been demonstrated to one gram-scale
已经开发了一种锌催化的C-(sp 3)-H将2-烷基氮杂芳烃添加到α-酮基酰胺中以提供掺入氮杂芳烃的α-羟基酰胺的方法,该方法分别在中等到极好的收率下使用了多种底物。在简单的酮存在下,α-酮酰胺的酮官能团的化学选择性烷基化是这种锌催化转化的关键优势。这种方法已被证明可以进行一克规模的合成。1 H NMR和D 2 O交换实验研究表明该反应通过Zn-烯酰胺中间体进行。
Indium-catalyzed C(sp<sup>3</sup>)–H functionalization of 2-methylazaarenes through direct benzylic addition to trifluoromethyl ketones
作者:Zaini Jamal、Yong-Chua Teo
DOI:10.1039/c4ra17182a
日期:——
The application of trivalent indium for the Lewisacid-catalyzedC(sp3)–H functionalization of 2-methylazaarenes is reported. InCl3 was discovered to catalyze the direct addition of the benzylic C–H bond in the azaarenes to trifluoromethyl ketones. An ample number of substrates were cogently demonstrated to give the products as trifluoromethylated alcohols whereby in some cases, up to quantitative
An enantioselective C−H addition to a C=C bond represents the most atom‐efficient route for the construction of chiral carbon–carbon skeletons, a central research topic in organic synthesis. We herein report the enantioselective yttrium‐catalyzed C(sp3)−H bond addition of 2‐methyl azaarenes, such as 2‐methyl pyridines, to various substituted cyclopropenes and norbornenes. This process efficiently afforded
C = C键上的对映选择性CH代表手性碳-碳骨架的构建中最有效的原子路线,这是有机合成的主要研究课题。我们在此报告了2-甲基氮杂芳烃(例如2-甲基吡啶)的对映选择性钇催化的C(sp 3)-H键加成到各种取代的环丙烯和降冰片烯上。此过程有效地提供了高收率和高对映选择性(高达ee高达97%)的手性吡啶基甲基官能化的环丙烷和降冰片烷衍生物新家族。