Methyl tert-butyl ether is found to undergo C–O bond cleavage in the formation of an iridium(III) methallyl at a cationic bis(phosphine) iridium complex. An exploration of this transformation has revealed a cyclometalated complex which was previously postulated to form reversibly in the first example of alkane dehydrogenation by a homogeneous transition-metal complex. The competence of this cyclometalated species in alkane dehydrogenation is demonstrated in a stoichiometric example, giving an isolable olefin dihydride. Detection and assignment of this elusive species confirms a previous hypothesis that reversible intramolecular phosphine cyclometalation can precede intermolecular alkane dehydrogenation.

中文翻译：

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铱双（膦）配合物在烷烃脱氢中的可逆环金属化和CO键断裂的证据。

发现甲基叔丁基醚在阳离子双（膦）铱配合物上形成铱（III）甲代烯丙基时会发生C-O键断裂。对这种转变的探索揭示了一种环金属化的配合物，该配合物先前被假定是在烷烃脱氢的第一个例子中被均相的过渡金属配合物可逆地形成。在化学计量的实例中证明了该环金属化物质在烷烃脱氢中的能力，给出了可分离的烯烃二氢化物。对这种难以捉摸的物种的检测和分配证实了先前的假设，即可逆分子内膦环金属化可先于分子间烷烃脱氢。