Azides and amines from Grignard reagents and tosyl azide

2,5‐Diamide‐Substituted Five‐Membered Heterocycles: Challenging Molecular Synthons

“…Thus, we turned to the protocol of Zanirato and co-workers, who reported, to the best of our knowledge, the only example of isolation of 2-azidothiophene. [56,57] In this two-step procedure, 2-bromothiophene is lithiated and then treated with TsN 3 to generate the corresponding triazene salt, which is then treated with Na 4 P 2 O 7 ·10 H 2 O to afford 2-azidothiophene. Li/halogen exchange was thus performed on 2,5-dibromothiophene with nBuLi, and the obtained dilithium thiolyl derivative was added to a solution of TsN 3 .…”

“…[44,45] They are commonly prepared from the corresponding amines, either via diazonium salt intermediates [46][47][48][49] or directly by treatment with triflyl azide. [56,57] In this two-step procedure, 2-bromothiophene is lithiated and then treated with TsN 3 to generate the corresponding triazene salt, which is then treated with Na 4 P 2 O 7 ·10 H 2 O to afford 2-azidothiophene. [52,53] The latter reaction was reported also to work for inactivated aryl halides at temperatures low enough to allow the survival of the azide, in the presence of proline [54] or a bisamine [55] as ligands.…”

Azides

“…(8) Azidoazomethine-tetrazole equilibrium [72,73]. (9) Azides and amines from Grignard reagents and tosyl azide [74]. (10) Preparation of triphenylsilyl azide [75].…”

Synthesis, reactivity, and electronic structure of multifarious, five-membered heteroaryl and heteroaroyl azides

“…Our long-term interest in this field started with the application of the synthetic method proposed by Smith to heteroaryl systems to produce aryl azides, 5 that is, the 'azido transfer' protocol. The protocol is based on the reaction of an aryl Grignard reagent with p-toluenesulphonyl azide (tosyl azide) to form a triazene-salt intermediate that can be fragmented into aryl azide and MgBr tosylate in a buffered solution of tetrasodium pyrophosphate (Na 4 P 2 O 7 ).…”