Synthesis of the First Resorcin[4]arene-Functionalized Triazolium Salts and Their Use in Suzuki–Miyaura Cross-Coupling Reactions

Catalysts

Rengan Ramesh¹  David Sémeril²  Dominique Matt² 

[1] Center for Organometallic Chemistry, School of Chemistry, Bharathidasan University, Tiruchirappalli, Tamilnadu 620 024, India;Synthèse Organométallique et Catalyse, Université de Strasbourg, UMR 7177 CNRS, 4 rue Blaise Pascal, 67008 Strasbourg, France;

关键词: resorcinarene;    triazolium salt;    Suzuki–Miyaura cross-coupling;   

DOI  :  10.3390/catal9040388

来源: DOAJ

【 摘 要 】

Two bulky triazolium salts, namely 1-{4(24),6(10),12(16),18(22)-tetramethylenedioxy- 2,8,14,20-tetrapentylresorcin[4]arene-5-yl}-4-phenyl-3-methyl-1H-1,2,3-triazolium tetrafluoro borate (1) and 1,4-bis{4(24),6(10),12(16),18(22)-tetramethylenedioxy-2,8,14,20-tetrapentyl resorcin[4]arene-5-yl}-3-methyl-1H-1,2,3-triazolium iodide (2), have been synthesized and assessed in the palladium-catalyzed Suzuki−Miyaura cross-coupling of aryl chlorides, with aryl boronic acids. As a general trend, the reaction rates obtained with 1 were significantly higher (up to 5 times) than those observed for 2, this mainly reflected a sterically more accessible metal center in the catalytic intermediates formed with 1. The presence of flexible pentyl chains in these intermediates, which might sterically interact with the metal center, when the latter adopts an exo-orientation with respect to the cavity, were likely responsible for the observed good performance.

【 授权许可】

Unknown