title: Reactive iron carbonyl reagents via reaction of metal alkoxides with Fe(CO)5 or Fe2(CO)9: synthesis of cyclobutenediones via double carbonylation of alkynes.
abstract: Alkoxy bases such as t-BuOK react with Fe(CO)(5) to give reactive iron carbonyl intermediates that in turn react with alkynes at 70 °C in THF to give 1,2-cyclobutenediones in 70-93% yields after CuCl(2)·2H(2)O oxidation. A novel 1,2-diacyloxyferrole derivative was isolated in the reaction of diphenylacetylene with Fe(CO)(5)/t-BuOK in the presence of acetyl chloride in contrast to the formation of a 1,4-diacyloxyferrole complex formed in the reaction using Fe(CO)(5)/Me(3)NO. The Fe(2)(CO)(9)/t-BuOK reagent system also converts the alkynes to corresponding cyclobutenediones in 63-90% yields under similar reaction conditions.
authors.affiliation: School of Chemistry, University of Hyderabad, Hyderabad 500046, India.
authors.forename: Mallesh
authors.initials: M
authors.lastname: Beesu
authors.forename: Mariappan
authors.initials: M
authors.lastname: Periasamy
mesh_terms: D000438:Alcohols / Q000737:chemistry*; D000480:Alkynes / Q000737:chemistry*; D018360:Crystallography, X-Ray; D003503:Cyclobutanes / Q000138:chemical synthesis* / Q000737:chemistry; D005296:Ferrous Compounds / Q000737:chemistry*; D007202:Indicators and Reagents / Q000737:chemistry; D058085:Iron Compounds / Q000737:chemistry*; D008670:Metals / Q000737:chemistry*; D015394:Molecular Structure; D010084:Oxidation-Reduction
chemical_list: D000438:Alcohols; D000480:Alkynes; D003503:Cyclobutanes; D005296:Ferrous Compounds; D007202:Indicators and Reagents; D058085:Iron Compounds; D008670:Metals; C059688:alkoxyl radical; C553737:cyclobutenone; C515100:iron pentacarbonyl