The Al/P based Frustrated Lewis Pair 1  is accessible on a facile route by reaction of the alkynylphosphine Mes2P-CC-C6H5 with di(tert-butyl)aluminum hydride. 1  is monomeric in the solid state and has a geminal arrangement of donor and acceptor sites. It was found to react with terminal alkynes by C-H bond activation [1] and with CO2 [1] or Ph-N=C=O by adduct formation [2]. An interesting feature is its singular capability to react as an efficient receptor for ion pairs such as alkali metal hydrides and to solubilize and activate those ionic compounds. These hydride adducts exhibit different structural motifs with lithium coordinated to phosphorus (2  ) and the softer sodium or potassium atoms interacting with the aromatic ring of a mesityl group (3  ) [3]. 1  is able to react as a phase transfer catalyst which is exemplified by the reaction of the sodium hydride adduct 3  with chloro-triphenylsilane [3]. Dehydrogenation is another important aspect of this chemistry, and vigorous gas evolution was observed even at low temperatures when 1  was treated with aminoboranes. Dimethylaminoborane gave an amidoborane adduct (4  ) at low temperature which spontaneously liberated the amidoborane ligand to yield a four-membered B2N2 heterocycle. This dehydrogenation reaction requires only catalytic quantities of compound 1 (0.4%). [1] Angew. Chem. Int. Ed. 2011  , 50, 3925.[2] Dalton Trans. 2012  , 41, 9033.[3] Angew. Chem. Int. Ed. 2012  , 51, 5911.

Al/P based frustrated Lewis pairs: Small molecule activation, ion pair receptors, hydride transfer and catalytic dehydrogenation

245th National Meeting (2013)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.