The Facile Synthesis of Lithium 2‐R‐Hydroquinolinide Complexes and Their High Activity toward ROP of ε‐Caprolactone

Abstract

Four lithium 2-R-hydroquinolinide complexes [1-(2-(R)-C 9 H 7 )NLi·THF 2 ] 2 (1 R = Me, 2 R = nBu) and [1-(8-(Me)-2-(Bu n )-C 9 H 6 )NLi·X] 2 (3 X = THF, 4 X = Et 2 O) were prepared by the nucleophilic addition reaction of quinoline and 8-methylquinoline with MeLi or Bu n Li, respectively. All complexes have been characterized through NMR spectroscopy. Complexes 2-4 were determined by X-ray crystallography. Interestingly, Li atom in 1 and 2 is tetracoordinate, whereas Li atom in 3 and 4 is threecoordinate. All these complexes showed super-high activity for [a]

Lithium anthraquinoids as catalysts in the ROP of lactide and caprolactone into cyclic polymers

“…The complex imposing a more sterically demanding situation exhibited a slightly higher catalytic activity than others under similar conditions. 24…”

“…The complex imposing a more sterically demanding situation exhibited a slightly higher catalytic activity than others under similar conditions. 24 Following the design and application of these complexes, the association between the structure and reactivity for the ROP process has been a point of discussion. The aggregation state of the catalytic species, the steric hindrance and the plausible electronic influence of the ligands can alter the catalytic performance of ROP catalysts.…”

Halogenated β‐diketiminato magnesium complexes: Preparation, characterization, and catalysis for ring‐opening polymerization of aliphatic lactones

“…As a powerful strategy for the preparation of polyester, the organometallics‐promoted ring‐opening polymerization (ROP) of aliphatic lactones has attracted great attentions 5–8 . To date, plenty of organometallics have been demonstrated as efficient catalysts for the ROP of lactones, such as alkali metals (Li, 9 K 10–11 ), alkaline‐earth metals (Mg, 12–18 Ca, 19 Ba 20 ), aluminum, 21–25 tin, 26 rare‐earth metals 27–34 and some transition metals (Ti, 35 Zr, 36 V, 37 Fe, 38–39 Zn 40–43 ). Among them, the magnesium‐based complex has attracted special attention due to its high activity and low toxicity.…”