Improved Preparation of Tetrahydroselenophene (Selenacyclopentane) and Tetrahydroteliajrophene (Tellur Acy Clopentane)

Abstract
Tetrahydroselenophene and tetrahydrotellurophene were prepared in yields between 80 to 90% by the reaction between disodium chalcogenides and 1,4-dibromobutane in a medium of aqueous sodium hydroxide in the presence of methyltrialkyl(C8-C10) ammonium chloride as the phase-transfer catalyst. The disodium chalcogenides synthesized from the elemental chalcogens and sodium formaldehyde-sulfoxylate in aqueous sodium hydroxide solution were used in situ.