Reversible 1,1-hydroaluminations and C-H activation in reactions of a cyclic (alkyl)(amino) carbene with alane.

Chem Commun (Camb)

Department of Chemistry, University of Toronto, 80 St. George St., Toronto, Ontario, M5S 3H6, Canada.

Published: July 2018

Varying the reaction ratio of cyclic (alkyl)(amino) carbene (cAACEt) with AlH3·NEtMe2 leads to the isolation of (cAACEtH)AlH2·NEtMe21 and (cAACEtH)2Al(μ-H)2AlH2·NEtMe22 and the first example of a monomeric dialkyl-aluminum hydride (cAACEtH)2AlH 3. VT and 1H-1H EXSY NMR experiments of 3 demonstrated the isomerization of the diastereomers of 3via the first instance of reversible hydride migration between the Al and the C center. In addition, heating solutions of 3 at 100 °C affords (cAACEtH)Al(CHC(Et)2CH2C(Me)2NC6H3(iPr)C(Me)CH2) 4 with loss of H2.

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http://dx.doi.org/10.1039/c8cc05013aDOI Listing

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