Efficient and Heteroselective Heteroscorpionate Rare-Earth-Metal Zwitterionic Initiators for ROP of rac-Lactide: Role of sigma-Ligand

	Efficient and Heteroselective Heteroscorpionate Rare-Earth-Metal Zwitterionic Initiators for ROP of rac-Lactide: Role of sigma-Ligand
	Mou, Zehuai ; Liu, Bo ; Liu, Xinli ; Xie,Hongyan ; Rong,Weifeng ; Li,Lei ; Li,Shihui ; Cui,Dongmei
刊名	macromolecules
	2014
卷号	47 期号:7 页码:2233-2241
关键词	RING-OPENING POLYMERIZATION YTTRIUM PHOSPHASALEN INITIATORS N STEREOSELECTIVE POLYMERIZATION RACEMIC LACTIDE STRUCTURAL-CHARACTERIZATION ISOPRENE POLYMERIZATION EPSILON-CAPROLACTONE ALUMINUM INITIATORS POLY(LACTIC ACID) O MULTIDENTATE LIGANDS
通讯作者	cui,dm
英文摘要	a series of oxophosphine (3,5-me(2)pz)(2)chp-(r)(2)o (pz = pyrazole; r = bu-t (hl1), cy (hl2)) and iminophosphine (3,5-me(2)pz)(2)chp(r)(2)nar = cy, ar = ph (hl3); r = ph, ar = ph (hl4), ar = 2,6-me-2-phenyl (hl5)) heteroscorpionate ligands were synthesized. abstraction of the methide proton of these ligands by rare-earth-metal tris(alkyl)s, ln(ch2sime3)(3)(thf)(2), afforded the corresponding zwitterionic bis(alkyl) complexes l(1-5)ln(ch2sime3)(2)(thf) (l-1, ln = y (1a), lu (1b); l-2, ln = y (2a), lu (2b); l-3, ln = y (3a), lu (3b); l-4, ln = y (4a), lu (4b); l-5, ln = y (5a), lu (5b), while metathesis reaction of the lithium salts of lil3 and lil4 with ycl3(thf)(2) or ybr3(thf)(2) followed by treatment with lich2sime3 and kn(sihme2)(2), respectively, afforded the first heteroscorpionate yttrium mixed halogen/alkyl or amido complexes l3-4y(cl)(ch2sime3)(thf) (l-3 (6a), l-4 (7a)), l3-4y(cl)(n(sihme2)(2))(thf) (l-3 (8a), l-4 (9a)), (ly)-y-4(br)(ch2sime3)(thf) (10a), and (ly)-y-4(br)(n(sihme2)(2))(thf) (11a). the structures of these complexes were well-defined, and the molecular structures of la, 2a, 3b, 4b, 5a, and 7a were further characterized by single crystal x-ray diffraction analysis. complexes 1-5 showed similar high activity toward the rop of rac-la at room temperature, and both the alkyl species participated in initiation, of which the lutetium complexes exhibited slightly higher selectivity than their yttrium analogues (p-r = 0.85-0.89 vs 0.80-0.84) despite the bulkiness of the ligands. interestingly, the mixed halogen complexes 6a-11a were single-site initiators, where the sigma-halogen moiety remaining on the central metal showed, for the first time, facilitating the heteroselectivity up to p-r = 0.98. this result sheds new light on designing specifically selective catalytic precursors.
收录类别	SCI
语种	英语
WOS记录号	WOS:000338807300006
内容类型	期刊论文
源URL	[http://ir.ciac.jl.cn/handle/322003/52087]
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	Mou, Zehuai,Liu, Bo,Liu, Xinli,et al. Efficient and Heteroselective Heteroscorpionate Rare-Earth-Metal Zwitterionic Initiators for ROP of rac-Lactide: Role of sigma-Ligand[J]. macromolecules,2014,47(7):2233-2241.
APA	Mou, Zehuai.,Liu, Bo.,Liu, Xinli.,Xie,Hongyan.,Rong,Weifeng.,...&Cui,Dongmei.(2014).Efficient and Heteroselective Heteroscorpionate Rare-Earth-Metal Zwitterionic Initiators for ROP of rac-Lactide: Role of sigma-Ligand.macromolecules,47(7),2233-2241.
MLA	Mou, Zehuai,et al."Efficient and Heteroselective Heteroscorpionate Rare-Earth-Metal Zwitterionic Initiators for ROP of rac-Lactide: Role of sigma-Ligand".macromolecules 47.7(2014):2233-2241.