27513-87-7Relevant articles and documents
Synthesis of 2-Acylselenophenes via Iodine-Promoted Nucleophilic Cyclization of [2-(Butylselanyl)phenyl]-propynols
Pistoia, Renan P.,Roehrs, Juliano A.,Back, Davi F.,Zeni, Gilson
, p. 3655 - 3665 (2015)
We describe the synthesis of [2-(butylselanyl)phenyl]propynols and their application as substrates in intramolecular iodine-promoted nucleophilic cyclization reactions for the preparation of 2-acylselenophenes. [2-(Butylselanyl)phenyl]propynols were prepared by nucleophilic aromatic substitution reactions of 2-halobenzaldehydes with lithium butylselenolate followed by alkynylation of the carbonyl function with lithium acetylides. Effects of solvent, temperature, reaction time and iodine amount on the efficiency of the cyclization reactions were investigated. The results demonstrated that the best yields of 2-acylselenophenes were obtained when iodine (1.1 equiv.) and ethanol (3 mL) at room temperature were applied to [2-(butylselanyl)phenyl]propynols. The utility of 2-acylselenophene derivatives was also studied through alkynylation of a carbonyl group to obtain the alkynol derivatives followed by an electrophilic cyclization reaction to give selenophene-fused aromatic compounds. The 2-acylselenophene was also applied as a substrate in cyanation reactions.
Synthesis of benzo[b]chalcogenophenes fused to selenophenesviaintramolecular electrophilic cyclization of 1,3-diynes
Hellwig, Paola S.,Guedes, Jonatan S.,Barcellos, Angelita M.,Jacob, Raquel G.,Silveira, Claudio C.,Lenard?o, Eder J.,Perin, Gelson
supporting information, p. 596 - 604 (2021/02/06)
We describe herein an alternative and transition-metal-free procedure for the access of benzo[b]chalcogenophenes fused to selenophenesviaintramolecular cyclization of 1,3-diynes. This efficient protocol involves a double cyclization of 1,3-diynyl chalcogen derivatives promoted by the electrophilic species of organoselenium generatedin situby the oxidative cleavage of the Se-Se bond of dibutyl diselenide using Oxone in acetonitrile as solvent in an open-flask at 80 °C. In this study, 15 selenophenes with broad substrate scope were prepared in moderate to excellent yields (55-98%) with short reaction times (0.5-3.0 h).
