Efficient Synthesis of a New Family of 2,6-Disulfanyl-9-Selenabicyclo[3.3.1]Nonanes

Abstract

The efficient synthesis of a new family of 2,6-disulfanyl-9-selenabicyclo[3.3.1]nonanes in high yields has been developed based on 9-selenabicyclo[3.3.1]nonane-2,6-dithiolate anion generated from bis-isothiouronium salt of 2,6-dibromo-9-selenabicyclo[3.3.1]nonane. The derivatives of 2,6-disulfanyl-9-selenabicyclo[3.3.1]nonane containing alkyl, allyl and benzyl moieties have been prepared in 90–99% yields by nucleophilic substitution of 9-selenabicyclo[3.3.1]nonane-2,6-dithiolate anion with alkyl, allyl and benzyl halides. The reaction of nucleophilic addition of 9-selenabicyclo[3.3.1]nonane-2,6-dithiolate anion to alkyl propiolates afforded 2,6-di(vinylsulfanyl)-9-selenabicyclo[3.3.1]nonanes. The conditions for regio- and stereoselective addition of 9-selenabicyclo[3.3.1]nonane-2,6-dithiolate anion to a triple bond of alkyl propiolates have been found. To date, not a single representative of 2,6-disulfanyl-9-selenabicyclo[3.3.1]nonanes has been described in the literature.

Click Chemistry of Selenium Dihalides: Novel Bicyclic Organoselenium Compounds Based on Selenenylation/Bis-Functionalization Reactions and Evaluation of Glutathione Peroxidase-like Activity

“…Along with the 1,3-dipolar cycloaddition reaction, unsubstituted acetylene was involved in the nucleophilic addition reaction of dithiolate anion 21 generated from bis-isothiuronium salt 20 . We previously obtained compound 20 by refluxing dibromo derivative 2 with a high excess of thiourea in acetonitrile [ 60 ]. Here, we report the preparation of this compound in 95% yield, at room temperature, at a stoichiometric ratio of the reagents and the synthesis of bis(vinylsulfanyl) derivative of 9-selenabicyclo[3.3.1]nonane 22 in 81% yield ( Scheme 10 ).…”

“…Earlier in this laboratory, selenium dichloride and dibromide were introduced for the first time into the synthesis of organoselenium compounds [ 51 ]. The use of these reagents in organic synthesis made it possible to obtain novel classes of organoselenium and heterocyclic compounds [ 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 ].…”

“…A number of efficient syntheses of novel organoselenium compounds were developed based on 2,6-dibromo-9-selenabicyclo[3.3.1]nonane ( 2 ) [ 56 , 57 , 58 , 59 , 60 , 61 ]. Inter alia , bis-pyridinium salt 3 was obtained by the reaction of nonane 2 with pyridine at room temperature in acetonitrile ( Scheme 1 ).…”