摘要
The reactions of R 2 AlX with one equivalent of 2,2′-methylene-bis-(4,6-di-tert-butylphenol) (MDBP-H 2 ) or 2,2′-methylene-bis-(4-methyl-6-tert-butylphenol) (MMBP-H 2 ) in oxygenated solvent afford monomeric four-coordinated compounds, XAl(MDBP)(S), 1-5 (1: R = Me, X = Br, S = Et 2 O; 2: R = Et, X = Cl, S = Et 2 O; 3: R = Me, X = Br, S = THF; 4: R = Et, X = Cl, S = THF; 5: R = X = Et, S = Et 2 O) or XAl(MMBP)(S), 6-8 (6: R = X = Et, S = Et 2 O; 7: R = X = i Bu, S = Et 2 O; 8: R = Et, X = Cl, S = Et 2 O). Crystal structures of 1, 2 and 7 demonstrate that the conformation of the eight-membered heterocycles containing aluminum is controlled by an unusual intramolecular C-H⋯O hydrogen bond. Et 2 AlCl or i Bu 3 Al reacts with one equivalent of 2,2′-ethylidene-bis-(4,6-di-tert-butylphenol) (EDBP-H 2 ) or MDBP-H 2 in toluene giving a dimeric four coordinate compound [CLAL(μ-EDBP] 2 , 9 or [ i BuAl(μ-MDBP)] 2 , 10. Some of these compounds have shown great catalytic activities toward the reaction of cyclopentadiene with methacrolein. © 1999 Elsevier Science S.A. All rights reserved.