960化工网
Bis(oxazolinyl)phenylborane: A Lewis acid-containing ligand for methide abstraction-based coordination to aluminum(III)†
James F. Dunne,Kuntal Manna,Jerzy W. Wiench,Arkady Ellern,Marek Pruski,Aaron D. Sadow
Dalton Transactions Pub Date : 10/27/2009 00:00:00 , DOI:10.1039/B911851A
Abstract

A compound that contains a Lewis acidic boron center and coordinating oxazoline groups, bis(4,4-dimethyl-2-oxazolinyl)phenylborane (PhB(OxMe2)2; 1), has been prepared and spectroscopically characterized. Solvent dependent 15N and 11B NMR spectroscopic properties and solid-state 11B NMR measurements provide support for intermolecular interactions involving Lewis acid and base sites. The bifunctional nature of oxazolinylborane 1 is demonstrated by its reaction with (AlMe3)2, which proceeds via methide abstraction by the boron and oxazoline coordination to aluminum to yield [2-PhMeB(OxMe2)2AlMe2] (2). Compound 2 contains a planar six-membered chelate ring, in contrast to related bis(pyrazolyl)boratoaluminum compounds that are puckered. Additionally, compound 2 and related bidentate tris(oxazolinyl)phenylborato dimethylaluminum are inert toward aluminum-methyl bond protonolysis. This robust nature suggested the possibility of using these oxazolinylboratoaluminum compounds in catalytic reactions, as is demonstrated by lactide ring-opening polymerization.

Graphical abstract: Bis(oxazolinyl)phenylborane: A Lewis acid-containing ligand for methide abstraction-based coordination to aluminum(III)
平台客服
平台客服
平台在线客服