32773-42-5Relevant articles and documents
FeCl3-Diorganyl dichalcogenides promoted cyclization of 2-alkynylanisoles to 3-chalcogen benzo[ b ]furans
Gay, Rafaela M.,Manarin, Flavia,Schneider, Caroline C.,Barancelli, Daniela A.,Costa, Michael D.,Zeni, Gilson
supporting information; experimental part, p. 5701 - 5706 (2010/10/03)
A general synthesis of 3-chalcogen benzo[b]furans from the readily available 2-alkynylanisoles, via FeCl3/diorganyl dichalcogenides intramolecular cyclization, has been developed. Aryl and alkyl groups directly bonded to the chalcogen atom were used as cycling agents. The results revealed that the reaction significantly depends on the electronic effects of substituents in the aromatic ring bonded to the selenium atom of the diselenide species. We observed that the pathway of reaction was not sensitive to the nature of substituents in the aromatic ring of anisole since both the electron-donating and the electron-withdrawing groups delivered the products in similar yields. In addition, the obtained heterocycles were readily transformed to more complex products by using a chalcogen/lithium exchange reaction with n-BuLi followed by trapping of the lithium intermediate with aldehydes, furnishing the desired secondary alcohols in good yields.
SYNTHESIS OF α-SELENOALKYLLITHIUM COMPOUNDS
Krief, A.,Dumont, W.,Clarembeau, M.,Bernard, G.,Badaoui, E.
, p. 2005 - 2022 (2007/10/02)
α-Phenylselenoalkyllithiums and α-methylselenoalkyllithiums have been prepared from the corresponding selenoacetals and alkyllithiums.Several features of this reaction are disclosed.For example, the reaction is more readily achieved on phenylselenoacetals than on methylseleno analogues.Those derived from hindered carbonyl compounds are less readily cleaved. s-BuLi/THF proved superior to n-BuLi in THF, itself better than n-BuLi in ether.