Reactions of (Arylimido)vanadium(V)–Trialkyl Complexes with Phenols: Effects of Arylimido Ligands and Phenols for Formation of the Vanadium Phenoxides
Abstract
Reactions of a series of (arylimido)vanadium(V) trialkyl complexes, V(NAr′)(CH_2SiMe_3)_3 (Ar′ = C_6H_5, 2-MeC_6H_4, 2,6-Me_2C_6H_3, 2,6-Cl_2C_6H_3), with various phenols (ArOH, Ar = 2,6-F_2C_6H_3, 2,6-Cl_2C_6H_3, 2,6-Me_2C_6H_3, 2,6-^iPr_2C_6H_3, 2-^tBuC_6H_4, 2,6-^tBu_2C_6H_3; 1.0 equiv) affording V(NAr′)(CH_2SiMe_3)_2(OAr) were conducted in C_6D_6 at 25 °C, and the effects of both arylimido ligands and phenols on the substitution rate were explored. Sterically hindered arylimido ligands showed lower reactivity, and the reaction proceeded in the order: Ar′ = 2,6-Me_2C_6H_3 < 2,6-Cl_2C_6H_3 < 2-MeC_6H_4< C_6H_5. This order is somewhat different from that obtained from the chemical shifts in V(NAr′)(CH_2SiMe_3)_3 in the ^(51)V NMR spectra. The conversions with various disubstituted phenols increased in the order: 2,6-^iPr_2C_6H_3OH < 2,6-Me_2C_6H_3OH < 2,6-Cl_2C_6H_3OH < 2,6-F_2C_6H_3OH, irrespective of the kind of arylimido ligands. The reactions of V(NAr′)(CH_2SiMe_3)_3 with 2,6-^tBu_2C_6H_3OH (1.0 or 3.0 equiv) did not take place even upon heating at 60 °C. These results suggest that the reactions proceed via coordination of ArOH toward vanadium, and the reactivity is highly dependent on steric bulk of both the arylimido ligand and the phenol.
Additional Information
© 2019 American Chemical Society. ACS AuthorChoice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. Received: February 25, 2019; Accepted: March 14, 2019; Published: March 25, 2019. This project was partly supported by Grant-in-Aid for Scientific Research on Innovative Areas ("3D Active-Site Science", No. 26105003) from the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan, and Grant-in-Aid for Scientific Research from the Japan Society for the Promotion of Science (JSPS, Nos 15H03812 and 18H01982). Authors express their gratitude to Profs. S. Komiya, K. Tsutsumi, and A. Inagaki (Tokyo Metropolitan Univ.) for discussion, and H.H. expresses her thanks to Prof. K. Tsutsumi for help in the crystallographic analysis. The authors declare no competing financial interest.Attached Files
Published - acsomega.9b00531.pdf
Supplemental Material - ao9b00531_si_001.pdf
Supplemental Material - ao9b00531_si_002.cif
Supplemental Material - ao9b00531_si_003.txt
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Additional details
- Eprint ID
- 94754
- Resolver ID
- CaltechAUTHORS:20190417-143132985
- 26105003
- Ministry of Education, Culture, Sports, Science and Technology (MEXT)
- 15H03812
- Japan Society for the Promotion of Science (JSPS)
- 18H01982
- Japan Society for the Promotion of Science (JSPS)
- Created
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2019-04-17Created from EPrint's datestamp field
- Updated
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2021-11-16Created from EPrint's last_modified field