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Abstract Pincer‐type nickel–aluminum complexes were synthesized using two equivalents of the phosphinoamide, [PhNCH2PiPr2]−. The Ni0–AlIIIcomplexes, {(MesPAlP)Ni}2(μ‐N2) and {(MesPAlP)Ni}2(μ‐COD), whereMesPAlP is (Mes)Al(NPhCH2PiPr2)2, were structurally characterized. The (PAlP)Ni system exhibited cooperative bond cleavage mediated by the two‐site Ni–Al unit, including oxidative addition of aryl halides, H2activation, and ortho‐directed C−H bond activation of pyridine N‐oxide. One intriguing reaction is the reversible intramolecular transfer of the mesityl ring from the Al to the Ni site, which is evocative of the transmetalation step during cross‐coupling catalysis. The aryl‐transfer product,(THF)Al(NPhCH2PiPr2)2Ni(Mes), is the first example of a first‐row transition metal–aluminyl pincer complex. The addition of a judicious donor enables the Al metalloligand to convert reversibly between the alane and aluminyl forms via aryl group transfer to and from Ni, respectively. Theoretical calculations support a zwitterionic Niδ−–Alδ+electronic structure in the nickel–aluminyl complex.
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Synthesis of Unsupported Primary Phosphido Complexes of Aluminum(III)
Abstract Primary phosphido complexes of aluminum(III) are rare, particularly those that are not supported by interactions with Lewis bases or stabilizing cations. Here we report two new examples of unsupported primary phosphido complexes of Al(III). The ancillary ligand on Al is a pincer ligand, diiminopyridine (denoted as I2P). Solid‐state structures show distorted tetrahedral geometry about Al and single bond character in the Al−P bond. Near infra‐red spectra display low energy absorption bands near 1050 nm that are consistent with pincer ligand – Al charge transfer transitions and metalloaromatic character in the “(I2P2−)Al” fragment of the molecules. The phosphido ligands lie out of the I2P ligand plane by up to 15° and this is consistent with our previous reports where π‐donor halide ligands occupy the fourth coordination site on Al.
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- Award ID(s):
- 1763821
- PAR ID:
- 10287111
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Zeitschrift für anorganische und allgemeine Chemie
- Volume:
- 647
- Issue:
- 18
- ISSN:
- 0044-2313
- Page Range / eLocation ID:
- p. 1824-1829
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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