Living ring-opening homo- and copolymerisation of ε-caprolactone and<scp>l</scp>-lactide by cyclic β-ketiminato aluminium complexes
作者:Yan Liu、Wei-Shi Dong、Jing-Yu Liu、Yue-Sheng Li
DOI:10.1039/c3dt52712c
日期:——
A series of novel aluminium complexes containing cyclic β-ketiminato ligands of type Me2AlO-[(ArNCHC4H4(C6H4))]} (3a, Ar = 2,6-iPr2C6H3; 3b, Ar = C6H5; 3c, Ar = C6F5) have been prepared in high yields. These complexes were identified by 1H, 13C NMR spectroscopy and elemental analysis. X-ray structural analyses for 3aâc revealed that these complexes have a distorted tetrahedral geometry around Al, and both bond distances and bond angles were considerably influenced by the ligand structure. These complexes were tested as catalyst precursors for ring-opening polymerisation of ε-caprolactone (ε-CL) and L-lactide (L-LA) in the presence of 2-propanol as an initiator. Complex 3a could polymerize ε-CL in a controlled manner with high efficiency. Based on the living characteristics, the preparation of well-defined block copolymers PCL-b-PLLA via sequential addition of monomers was performed by 3a. Note that complex 3c exhibited rather high catalytic activity for the ROP of L-LA with narrow molecular weight distribution. The monomer conversion reached completion only in 4 h when the L-LA/Al molar ratio was 100 at 80 °C. PLLA-b-PCL copolymers were thus easily produced by 3c.
Synthesis of dimethylcobalt(III) complexes containing trimethylphosphine and 2-formyl-phenolato- or 2-formyl-enolato(O:O) ligands
作者:Xiaoyan Li、Hongjian Sun、Alexandra Brand、Hans-Friedrich Klein
DOI:10.1016/j.ica.2005.05.016
日期:2005.8
Substituted salicylaldehydes [(C6HRRR3)-R-1-R-2(CHO)(OH)] react with CoMe3(PMe3)(3) to afford 6-coordinate (cis-dimethyl)(2-formyl-phenolato)trans-bis(trimethylphosphine)cobalt(III) compounds CO[(C6HRRR3)-R-1-R-2 (CHO)(O)Me-2](PMe3)(2) (1: R-1 = H; R-2 = Me; R-3 = tert-Bu; 2: R-1, R-2 = C6H4; R-3 = H). Accordingly, substituted enolated malonic dialdehydes (CHO-CR4 = CR5-OH) react with CoMe3(PMe3)(3) to afford 6-coordinate (cis-dimethyl)(2-formyl-enolato)trans-bis(trimethylphosphine)cobalt(III) compounds Co((CHO-CR4=CR5-O)(Me)(2)](PMe3)(2) (3: R-4, R-5 = (CH2)(2)C6H4; 4: R-4 = R-5 = C6H5). In the molecular structure of 4, the cobalt atom is centred in an octahedral coordination geometry brought about by a six-membered chelate ring (O:O-ligand), cis-dimethyl and trans-trimethylphosphine groups. A reaction mechanism is suggested. (c) 2005 Elsevier B.V. All rights reserved.
DOPAMINE RECEPTOR SUBTYPE LIGANDS
申请人:MERCK SHARP & DOHME LTD.
公开号:EP0665840A1
公开(公告)日:1995-08-09
US5670522A
申请人:——
公开号:US5670522A
公开(公告)日:1997-09-23
[EN] DOPAMINE RECEPTOR SUBTYPE LIGANDS<br/>[FR] LIGANDS POUR LES SOUS-TYPES DE RECEPTEURS DE DOPAMINE
申请人:MERCK SHARP & DOHME LIMITED
公开号:WO1994010162A1
公开(公告)日:1994-05-11
(EN) Fused tricyclic heteroaromatic compounds of formula (I) wherein one of X and Y represents nitrogen, and the other of X and Y represents oxygen, sulphur or N-R2; Q represents a substituted five- or six- membered monocyclic heteroaliphatic ring which contains one nitrogen atom as the sole heteroatom and is linked to the five-membered heteroatomic ring containing the moieties X and Y via a carbon atom as well as substituted 3,4-dihydro-1-hydroxy-2-oxomethyl-naphthalene precursors thereto, are ligands for dopamine receptor subtypes within the body and are therefore useful in the treatment of disorders of the dopamine system, in particular schizophrenia.(FR) Des composés hétéroaromatiques tricycliques fusionnés de formule (I), où de X et Y l'un représente azote, et l'autre représente oxygène, soufre ou N-R2, Q représente un cycle hétéroaliphatique monocyclique à cinq ou six membres, contenant un atome d'azote comme le seul hétéroatome et lié au cycle hétéroatomique à cinq branches contenant les fractions X et Y par l'intermédiaire d'un atome de carbone, ainsi que leurs précurseurs substitués de 3,4-dihydro-1-hydroxy-2-oxométhyl-naphtalène, sont des ligands pour les sous-types de récepteurs de dopamine dans le corps, et s'avèrent donc utiles pour le traitement des troubles du système dopamine, et en particulier pour le traitement de la schizophrénie.