Facile Generation of Aluminum 1,2-Dihydropyridyl and Hydroxyl Derivatives from an Aluminum Cyclopropene Analogue

Abstract

Reaction of LAl(η2-Me3SiC2SiMe3) (1; L = HC[(CMe)(NDipp)]2, Dipp = 2,6-iPr2C6H3) with pyridine afforded the (1,2-dihydropyridyl)aluminum species LAl[C2(SiMe3)2CHN(C4H4)] (2), having an AlC3N five-membered ring, as a major product via insertion into one of the Al−C bonds, while hydrolysis of 1 at low temperature resulted in ring cleavage to yield the monomeric aluminum alkenyl hydroxide LAl(OH)[C(SiMe3)CH(SiMe3)] (3). The molecular structures of 2 and 3 were determined by X-ray single-crystal analysis.

An Unusual and Facile Synthetic Route to Alumoles

“…We have utilized the chelate ligand to coordinately stabilize the Al center and successfully prepared the aluminacyclopropenes L 1 Al(η 2 ‐C 2 R 2 ) (L 1 =CH(CMeNAr) 2 , Ar=2,6‐ i Pr 2 C 6 H 3 ; R=H, Ph, SiMe 3 , Me) . Other organic heterocycles of composition AlC 2 N, AlC 3 , AlC 3 O, AlC 3 N, and Al 2 C 3 S have been reported. However, attempts to synthesize alumoles by alkyne‐insertion reactions were not successful .…”

Reaction of sterically encumbered phenols, TEMPO-H, and organocarbonyl insertion reactions with L-AlH2(L = HC(MeCNDipp)2, Dipp = 2,6-diisopropylphenyl)

“…This is in line with other bdiketiminate-based terminal aluminum monohydroxides in the literature. [33][34][35][36][37][38][39][40][41][42]…”

Ring‐Opening Polymerization of ε‐Caprolactone Initiated by Aluminium Complexes Based on Pyridine‐Substituted Asymmetric β‐Diketiminate Ligands

“…Many different types of ligands, for example, salen, Schiff base, ketiminate, etc., have been used as ancillary ligands to initiate the ROP of ε‐caprolactone. Aluminium complexes with β‐diketiminate ligands have been reported extensively; however, their applications in the ROP of ε‐caprolactone are still less explored . β‐Diketiminate is a kind of large π‐electron‐rich ligand, which can effectively stabilize coordinatively ‐unstable or coordinatively unsaturated central metals.…”