T. Ooi et al., DILITHIUM 2,2'-METHYLENEBIS(4,6-DI-TERT-BUTYLPHENOXIDE) AS A BIDENTATE LEWIS-ACID IN ORGANIC-SYNTHESIS, Tetrahedron letters, 39(22), 1998, pp. 3745-3748
Dilithium 2,2'-methylenebis(4,6-di-tert-butylphenoxide) can be success
fully utilized as a bidentate Lewis acid for simultaneous coordination
to carbonyl groups, thereby accelerating the Diels-Alder reactions. T
he double activation ability of the bidentate lithium reagent toward c
arbonyls is emphasized in comparison with the corresponding monodentat
e lithium reagent. (C) 1998 Elsevier Science Ltd. All rights reserved.