1429632-84-7Relevant articles and documents
Effect of ancillary (aminomethyl)phenolate ligand on efficacy of aluminum-catalyzed glucose dehydration to 5-hydroxymethylfurfural
Saang'onyo, Daudi,Parkin, Sean,Ladipo, Folami T.
, p. 153 - 162 (2018)
Air-stable dimethylaluminum complexes LRAlMe2 that contain (aminomethyl)phenolate (LR) ligands were prepared in high yield. NMR data and X-ray crystallographic characterization of the molecular structures of several of the complexes confirmed bidentate coordination of the (aminomethyl)phenolate ligand to aluminum. Efficient aluminum catalysts for glucose dehydration to HMF were generated via modification of the (aminomethyl)phenolate ligand. LRAlMe2 complexes containing bidentate (aminomethyl)phenolate ligands with an aryl substituent on the amino moiety are efficient catalysts for glucose dehydration to HMF in ionic liquid solvents. In [EMIM]Br and [BMIM]Br, the reaction proceeds at 120 °C to very high conversion in 2 h to produce HMF with 60–63% selectivity and in 58–60% yield. Evidently, LRAlMe2 complexes catalyze glucose isomerization to fructose at ≥120 °C while the HMF yield depends on the degree of competing HMF loss to humins formation. These results indicate that additional studies of ancillary ligand effects on aluminum-catalyzed glucose dehydration are needed to improve knowledge of structure–function relationships that are key to increasing the efficiency of aluminum catalysts for dehydration of glucose (and ultimately cellulose) to HMF.
Aluminum complexes of bidentate phenoxy-amine ligands: Synthesis, characterization and catalysis in ring-opening polymerization of cyclic esters
Wang, Yuan,Ma, Haiyan
, p. 23 - 28 (2013/05/21)
A series of aluminum complexes 1a-5a bearing bidentate phenoxy-amine ligands were synthesized and characterized by NMR spectroscopy and elemental analyzes. The variation of the ortho-substituent of phenoxy moiety and the amino group of the ancillary ligands has crucial influence on the stoichiometric structure of the obtained aluminum complexes. Reaction of 2-(N-benzyl-N-R 3-aminomethyl)-4-R2-6-R1-phenols (R1 = tBu, R2 = Me, R3 = ethyl, 1; R1 = R2 = cumyl, R3 = ethyl, 2; R1 = R2 = cumyl, R3 = tBu, 3) with either one or half equivalent of AlMe3 exclusively afforded monoligated complexes L Bu,EtAlMe2 (1a), LCumyl,EtAlMe2 (2a) and LCumyl,BuAlMe2 (3a), whereas the treatment of 2-(N-benzyl-N-R3-aminomethyl)-4,6-dichlorophenols (R3 = ethyl, 4; R3 = tBu, 5) with 0.5 equivalent of AlMe 3 resulted in the formation of (LCl,Et)2AlMe (4a) or (LCl,Bu)2AlMe(HLCl,Bu) (5a) respectively. All of these aluminum methyl complexes can efficiently polymerize rac-lactide to atactic polymers and actively initiate the ring-opening polymerization of ε-caprolactone.
