abstract
A novel triazole bridged cobalt fluorophosphate coordination polymer with the formula {Co-5(1,2,4-triazole)(2)(OH)(2)(PO3F)(4)}(n) has been synthesized. Single crystal X-ray studies reveal that the compound comprises of Co-5 clusters which ultimately build the whole framework, here all cobalt centers are in octahedral geometry established from continuous shape analysis. All the cobalt centers are in Co(II) oxidation state and the results are supported by the bond valence sum (BVS) calculation. The sample has been characterized by single crystal X-ray, powder X-ray, FTIR and TGA analysis. The compound was tested for olefin catalysis performance and magnetism. Magnetization measurements reveal overall antiferromagnetic interactions among the Co(II) ions. The compound is very active in the catalytic transformation of olefins to their corresponding epoxides. Catalytic epoxidation studies reveal that cyclohexene and styrene can be converted up to 97 % with almost 65 % selectivity of products with higher TON numbers.
keywords
OLEFIN EPOXIDATION; METAL-COMPLEXES; OXIDATION; PHOSPHATES; FRAMEWORK
subject category
Chemistry
authors
Sen, R; De, SDP; dos Santos, AM; Escobar, LBL; Brandao, PC; Paz, FAA; Reis, MS; Lin, Z
our authors
Filipe Alexandre Almeida Paz
Principal Researcher
Paula Cristina Ferreira da Silva Brandão
Assistant Researcher
Zhi Lin
Principal ResearcherProjects
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
CICECO - Aveiro Institute of Materials (UIDP/50011/2020)
Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)
acknowledgements
R. S. thanks DST-SERB for ECR grant (ECR/2016/001572), and Adamas University (AU/R&D/SEED/03/03-2020-21). The UA researchers acknowledge the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 and LA/P/0006/2020, financed by national funds through the Portuguese Foundation for Science and Technology/MCTES. MSR thanks CNPq and FAPERJ. A portion of this research was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility.