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Lewis Superacidic Tellurenyl Cation-Induced Electrophilic Activation of an Inert Carborane.

ABSTRACT: The aryltellurenyl cation [2-(tBuNCH)C₆ H₄ Te]⁺ , a Lewis super acid, and the weakly coordinating carborane anion [CB₁₁ H₁₂ ]^- , an extremely weak Brønsted acid (pK_a =131.0 in MeCN), form an isolable ion pair complex [2-(tBuNCH)C₆ H₄ Te][CB₁₁ H₁₂ ], in which the Brønsted acidity (pK_a 7.4 in MeCN) of the formally hydridic B-H bonds is dramatically increased by more than 120 orders of magnitude. The electrophilic activation of B-H bonds in the carborane moiety gives rise to a proton transfer from boron to nitrogen at slightly elevated temperatures, as rationalized by the isolation of a mixture of the zwitterionic isomers 12- and 7-[2-(tBuN{H}CH)C₆ H₄ Te(CB₁₁ H₁₁ )] in ratios ranging from 62 : 38 to 80 : 20.

SUBMITTER: Hejda M

PROVIDER: S-EPMC8596995 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Lewis Superacidic Tellurenyl Cation-Induced Electrophilic Activation of an Inert Carborane.

Hejda Martin M Duvinage Daniel D Lork Enno E Lyčka Antonín A Černošek Zdeněk Z Macháček Jan J Makarov Sergey S Ketkov Sergey S Mebs Stefan S Dostál Libor L Beckmann Jens J

Chemistry (Weinheim an der Bergstrasse, Germany) 20210928 59

The aryltellurenyl cation [2-(tBuNCH)C6 H4 Te]+ , a Lewis super acid, and the weakly coordinating carborane anion [CB11 H12 ]- , an extremely weak Brønsted acid (pKa =131.0 in MeCN), form an isolable ion pair complex [2-(tBuNCH)C6 H4 Te][CB11 H12 ], in which the Brønsted acidity (pKa 7.4 in MeCN) of the formally hydridic B-H bonds is dramatically increased by more t ...[more]

PMID: 34495561

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