Ruthenium-nickel heterobimetallic complex as a bifunctional catalyst for ROMP of norbornene and ethylene polymerization

Author(s)

Masson, Gustavo H. C. ^[1] ; Cruz, Thais R. ^[1] ; Gois, Patrik D. S. ^[1] ; Martins, Daniele M. ^[2] ; Lima-Neto, Benedito S. ^[2] ; Oliveira, Guedmiller S. ^[3] ; Machado, Antonio E. H. ^[3] ; Bernardo-Gusmao, Katia ^[4] ; Goi, Beatriz E. ^[1] ; Carvalho-Jr, Valdemiro P.

Affiliation

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

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

^[3] Univ Fed Uberlandia, Inst Quim, POB 593, BR-38400089 Uberlandia, MG - Brazil

^[4] Univ Fed Rio Grande do Sul, Inst Quim, POB 15003, BR-91501970 Porto Alegre, RS - Brazil

• Document type: Journal article
• Source: NEW JOURNAL OF CHEMISTRY; v. 45, n. 26, p. 11466-11473, JUL 14 2021.
• Web of Science Citations: 0

Abstract

Monometallic {[}RuCl2(eta(6)-p-cymene)(pipNH(2))] (mono-Ru) and heterobimetallic {[}RuCl2(eta(6)-p-cymene)]{[}(mu-Schiff-pip)Ni(PPh3)Cl] (Ru-Ni) complexes were successfully synthesized. They were fully characterized by FTIR, UV-Vis, and NMR spectroscopic studies, elemental analysis, cyclic voltammetry and computational studies. Complex Ru-Ni was additionally characterized by MALDI-TOF mass spectrometry. The polynorbornene (polyNBE) syntheses via ROMP using mono-Ru and Ru-Ni as pre-catalysts in the presence of ethyl diazoacetate (EDA) were evaluated at different {[}EDA]/{[}Ru] ratios, time periods (5-60 min) and temperatures (25 and 50 degrees C). Higher yields of polyNBE were obtained using {[}NBE]/{[}Ru] = 5000 and 5 mu L of EDA at 50 degrees C for 60 min. Under these conditions, mono-Ru exhibited higher catalytic activity than Ru-Ni, reaching 50 and 40% yield, respectively. Hence, a strong steric influence of Ru-Ni on the catalytic activity was demonstrated. The order of magnitude of 10(5) g mol(-1) was measured by SEC for M-n and D values ranging from 1.64 to 3.70 for mono-Ru and from 1.26 to 2.40 for Ru-Ni. The catalytic activity of Ru-Ni on ethylene polymerization was evaluated at different {[}Al]/{[}Ni] ratios, temperatures (20-60 degrees C) and reaction times (3-12 h) using MAO as the co-catalyst. Ru-Ni was able to provide an activity of 71.40 kg PE (mol Ni)(-1) h(-1) at 40 degrees C after 3 h in a {[}Al]/{[}Ni] molar ratio of 2100, 7 mu mol of catalyst in 25 mL of toluene and 116 psi ethylene pressure. (AU)

• FAPESP's process: 18/19395-9 - Synthesis of new organometallic complexes of Fe (III), Co (III) and Ni (III) coordinated to asymmetric Schiff bases to mediate photo-OMRP
• Grantee: Beatriz Eleutério Goi Carvalho
• Support Opportunities: Regular Research Grants
• 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