Heteroscorpionate Rare-Earth Metal Zwitterionic Complexes: Syntheses, Characterization, and Heteroselective Catalysis on the Ring-Opening Polymerization of rac-Lactide

	Heteroscorpionate Rare-Earth Metal Zwitterionic Complexes: Syntheses, Characterization, and Heteroselective Catalysis on the Ring-Opening Polymerization of rac-Lactide
	Zhang ZC ; Cui DM
刊名	chemistry-a european journal
	2011
卷号	17 期号:41 页码:11520-11526
关键词	RACEMIC LACTIDE CYCLIC ESTERS STEREOSELECTIVE POLYMERIZATION COORDINATION CHEMISTRY BOROHYDRIDE COMPLEXES ALUMINUM COMPLEXES ALKYL COMPLEXES LIGANDS SCANDIUM INITIATORS
ISSN号	0947-6539
通讯作者	cui dm
中文摘要	novel neutral phosphine-modified heteroscorpionate ligand (3,5-me(2)pz)(2)chpph2 (1) and its derivatives oxophosphine (2) and iminophosphine (3) heteroscorpionates were synthesized for the first time. these neutral heteroscorpionate ligands displayed unique chemistry towards rare-earth metal tris(alkyl)s [ln(ch2sime3)(3)(thf)(2)] (ln=y, lu, sc). the reaction between compound 1 and [ln-(ch2sime3)(3)(thf)(2)] afforded heteroscorpionate rare-earth metal trialkyl adduct complexes 4a-c. compounds 2 and 3 were treated with [ln-(ch2sime3)(3)(thf)(2)] to give the unprecedented zwitterionic heteroscorpionate rare-earth metal dialkyls 5 and 6, respectively. in the process, the heteroscorpionates transferred to the carbanions by means of methine c-h bond cleavage that was attributed to the presence of the electron-withdrawing groups. in addition the ligand and central metal showed a concerted effect on both the catalytic activity and specific selectivity of complexes 4-6 for the ring-opening polymerization (rop) of rac-lactide (rac-la). all the adduct complexes 4 were nonselective and gave atactic polylactide (pla), probably due to the dissociation of ligand 1 from the active metal center during the polymerization. strikingly, zwitterionic complexes 5 catalyzed rapid rop of rac-la to produce plas with heterotacticity up to 0.87. however, the zwitterionic complexes 6 were less active and less selective than 5, which might be on account of the stronger coordination of the tetradentate ligand. complexes 5 represent rare examples of the selective rop of rac-la mediated by rare-earth metal complexes supported by non-bisphenolate ligands.
收录类别	SCI收录期刊论文
语种	英语
WOS记录号	WOS:000297014400020
公开日期	2012-06-08
内容类型	期刊论文
源URL	[http://ir.ciac.jl.cn/handle/322003/44311]
专题	长春应用化学研究所_长春应用化学研究所知识产出_期刊论文
推荐引用方式 GB/T 7714	Zhang ZC,Cui DM. Heteroscorpionate Rare-Earth Metal Zwitterionic Complexes: Syntheses, Characterization, and Heteroselective Catalysis on the Ring-Opening Polymerization of rac-Lactide[J]. chemistry-a european journal,2011,17(41):11520-11526.
APA	Zhang ZC,&Cui DM.(2011).Heteroscorpionate Rare-Earth Metal Zwitterionic Complexes: Syntheses, Characterization, and Heteroselective Catalysis on the Ring-Opening Polymerization of rac-Lactide.chemistry-a european journal,17(41),11520-11526.
MLA	Zhang ZC,et al."Heteroscorpionate Rare-Earth Metal Zwitterionic Complexes: Syntheses, Characterization, and Heteroselective Catalysis on the Ring-Opening Polymerization of rac-Lactide".chemistry-a european journal 17.41(2011):11520-11526.