In situ-generated arene-ruthenium catalysts bearing cycloalkylamines for the ring-opening metathesis polymerization of norbornene

Author(s)

Oliveira, Douglas P. ^[1] ; Cruz, Thais R. ^[1] ; Martins, Daniele M. ^[2] ; Maia, Pedro Ivo S. ^[3] ; Machado, Antonio E. H. ^[4] ; Bogado, Andre L. ^[5] ; Goi, Beatriz E. ^[1] ; Lima-Neto, Benedito S. ^[2] ; Carvalho-Jr, Valdemiro P.

Affiliation

^[1] UNESP Univ Estadual Paulista, Fac Ciencias & Tecnol, BR-19060900 Presidente Prudente, SP - Brazil

^[2] Univ Sao Paulo, Inst Quim Sao Carlos, BR-13560970 Sao Carlos, SP - Brazil

^[3] Univ Fed Triangulo Mineiro, Dept Quim, BR-38025440 Uberaba, MG - Brazil

^[4] Univ Fed Uberlandia, Inst Quim, POB 593, BR-38400089 Uberlandia, MG - Brazil

^[5] Univ Fed Uberlandia, Inst Ciencias Exatas & Nat Pontal, BR-38304402 Ituiutaba, MG - Brazil

• Document type: Journal article
• Source: CATALYSIS TODAY; v. 381, p. 34-41, DEC 1 2021.
• Web of Science Citations: 1

Abstract

Arene-ruthenium complexes of type {[}RuCl2(p-cymene)(cyclo-alkylamine)], where alkyl is pentyl (1), hexyl (2), heptyl (3) or octyl (4), were successful synthetized and applied as pre-catalysts in ROMP of norbornene (NBE). From experiments as a function of temperature and NBE loads, the yields increased with increasing cyclo-alkyl ring size (4 > 3 > 2 > 1). This was associated with steric-electronic features of the amine ligands. The highest yields of polyNBE were obtained with {[}NBE]/{[}Ru] molar reaction ratio = 5000/1 in the presence of EDA at 50 degrees C for 60 min, with molecular weight range of 3.6-5.9 x 10(4) g mol(-1) and D of 1.6-2.3. Characterization data obtained from CHN elemental analysis, spectroscopic techniques (FTIR, UV-vis, and H-1- and C-13(H-1] NMR), cyclic voltammetry, computational studies, and single crystal diffraction for complexes 2 and 4 were useful for understanding the pre-catalyst behavior. Thermodynamic parameters from DFT-calculation corroborate a ROMP process via a dissociative mechanism. (AU)

• FAPESP's process: 18/06340-1 - Bimetallic complexes of ruthenium(II) and nickel(II): coupling of mechanistically-incompatible reactions using multifunctional catalysts via tandem catalysis
• Grantee: Valdemiro Pereira de Carvalho Júnior
• Support Opportunities: Regular Research Grants
• FAPESP's process: 17/06329-5 - Development of ruthenium complexes with ammines as ancillary ligands for homogeneous catalysis of ring opening metathesis polymerization of cyclic olefins
• Grantee: Benedito dos Santos Lima Neto
• Support Opportunities: Regular Research Grants