| Summary: | 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-1<i>H</i>-1,2,3-triazolium tetrafluoro borate (<b>1</b>) 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-1<i>H</i>-1,2,3-triazolium iodide (<b>2</b>), 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 <b>1</b> were significantly higher (up to 5 times) than those observed for <b>2</b>, this mainly reflected a sterically more accessible metal center in the catalytic intermediates formed with <b>1</b>. 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.
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