Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH 5304, CH-1015 Lausanne, Switzerland.
Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH 5304, CH-1015 Lausanne, Switzerland;, Email:
Chimia (Aarau). 2021 Apr 28;75(4):329-332. doi: 10.2533/chimia.2021.329.
The azido group occupies an important position in modern organic chemistry, broadly used as amine surrogates and as anchors in bioconjugation. Despite their importance, examples of selective direct azidation of inert C(sp³)-H bonds remain limited and often require strong oxidative conditions. Herein, we highlight the use of -acyl oximes and -acyloxy imidates as directing groups for the selective iron-catalysed azidation of C(sp³)-H bond with trimethylsilyl azide, giving access to various γ-azido ketones and β-azido alcohols in moderate to excellent yields. The iron catalyst is assumed to play a dual role in these catalytic processes: as a reductant to generate the reactive iminyl and imidate radicals, respectively, and as a redox centre to mediate the azido transfer to the translocated carbon radical.
叠氮基团在现代有机化学中占有重要地位，广泛用作胺的替代物和生物偶联中的连接物。尽管它们很重要，但选择性地直接对惰性 C(sp³)-H 键进行叠氮化的例子仍然有限，而且通常需要很强的氧化条件。在此，我们强调了 -酰基肟和 -酰氧基异氰酸酯作为导向基团，在铁催化下用三甲基硅基叠氮化物选择性地对 C(sp³)-H 键进行叠氮化，以中等至优异的收率得到各种γ-叠氮酮和β-叠氮醇。铁催化剂在这些催化过程中发挥双重作用：作为还原剂分别生成反应性亚氨基和异氰酸酯自由基，以及作为氧化还原中心介导叠氮基转移到迁移的碳自由基上。
