Gold‐Catalyzed Synthesis of Tetrazoles from Alkynes by CC Bond Cleavage

Abstract

Golden duality: Tetrazoles are formed by the reaction of alkynes with TMSN3 (TMS=trimethylsilyl) in the presence of iPrOH and the gold(I) catalyst [JohnPhosAu(MeCN)]SbF6. In this transformation gold plays a dual role, first activating the alkyne and then generating a Brønsted acid in situ.

[3+2] Cycloaddition of azide with aldehyde hydrazone through an aminyl radical-polar crossover strategy

“…6 In 2007, Echavarren and coworkers reported an elegant synthesis of tetrazoles from terminal alkynes by gold-catalyzed C ≡ C bond cleavage. 7 Recently, Jiao and Shi group realized the gold-catalyzed nitrogenation of alkynes by C-C and C≡C bond cleavages for the direct synthesis of amino tetrazoles (Scheme 1b). 8 Both reactions proposed an active C=N intermediate resulting from C≡C bond cleavage.…”

Meeting the Challenge of Intermolecular Gold(I)‐Catalyzed Cycloadditions of Alkynes and Allenes

“…59 Terminal alkynes were found to cyclize with TMSN 3 to give tetrazoles involving a C–C bond cleavage with concomitant insertion of four nitrogen atoms. The addition of i PrOH increased significantly the yield of the reaction.…”

“…59, 60 A Brønsted acid-catalyzed protodemetalation followed by migration of the R group forms the nitrilium cation ( 45 - II ). Competitive migration of the methyl group takes place if the substituent on the alkyne moiety is an alkyl chain.…”

Oxidative Addition of Carbon–Carbon Bonds to Gold

“…[22] The properties of the thereby generated cationic organogold(III) complexes are currently under investigation.…”