Opening of Epoxide Rings Catalyzed by Niobium Pentachloride

Abstract

The behavior of several epoxides when treated with NbCl₅ was studied. In general, the studied epoxides reacted rapidly with NbCl₅, giving, in most cases, more than one product (chlorohydrins, products containing solvent residues, as well as rearrangement products). A detailed study was performed to verify the effects of the temperature (rt, 0°C, or −78°C) and of the NbCl₅ molar concentration on the composition of the products, yield, and time required for the reactions.

Keywords:

• epoxides
• Lewis acid
• niobium pentachloride

Acknowledgments

The authors thank the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP), the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), the Coordenadoria de Aperfeiçoamento de Pessoal do Nível Superior (CAPES), and the Financiadora de Estudos e Projetos (FINEP) for financial support. We also thank CBMM–Companhia Brasileira de Mineralogia e Mineração for NbCl₅ samples.