Vanadium(V) Arylimido Alkylidene N‑Heterocyclic Carbene Alkyl and Perhalophenoxy Alkylidenes for the Cis, Syndiospecific Ring Opening Metathesis Polymerization of Norbornene
Vanadium(V) arylimido alkylidene N-heterocyclic carbene (NHC) alkyl complexes of the type, V(N-2,6-R2C6H3)(CHSiMe3)(CH2SiMe3)(NHC), [R = Me (1a–c), Cl (2a,b); NHC = 1,3-bis(2,6-dimethylphenyl)imidazol-2-ylidene (IXy, a), 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene (IDipp, b), 1,3-bis(...
Saved in:
Published in | Organometallics Vol. 40; no. 13; pp. 2017 - 2022 |
---|---|
Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
American Chemical Society
12.07.2021
|
Online Access | Get full text |
Cover
Loading…
Summary: | Vanadium(V) arylimido alkylidene N-heterocyclic carbene (NHC) alkyl complexes of the type, V(N-2,6-R2C6H3)(CHSiMe3)(CH2SiMe3)(NHC), [R = Me (1a–c), Cl (2a,b); NHC = 1,3-bis(2,6-dimethylphenyl)imidazol-2-ylidene (IXy, a), 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene (IDipp, b), 1,3-bis(cyclohexyl)imidazol-2-ylidene (ICy, c)], and the perhalophenoxy substituted alkylidenes, V(N-2,6-Cl2C6H3)(CHSiMe3)(OC6X5)(IXy) [X = F (3), Cl (4)], have been prepared. The catalytic activities in the ring opening metathesis polymerization (ROMP) of norbornene (NBE) by 1a–c and 2a,b increased by addition of C6X5OH (1.0 equiv). The perhalophenoxides 3 and 4 exhibited superior activities with turnover frequencies (TOFs) up to 208 s–1. The resultant polymers possessed high molecular weights (M n up to 9.56 × 105) with cis-syndiotactic stereoregularity up to 98%. |
---|---|
ISSN: | 0276-7333 1520-6041 |
DOI: | 10.1021/acs.organomet.1c00271 |