Thiolysis of Aziridines

Aminosulfides, important building blocks for the synthesis of various bioactive molecules, can be prepared by the thiolysis of aziridines in the presence of Bi(OTf)3 (5 mol%) [36]. Even though Lewis acids such as boron trifluoride etherate and zinc chloride, as well as Bronsted acids such as trifluoromethanesulfonic acid, have been employed as acid catalysts, these methods suffer from disadvantages like the use of stoichiometric amount of catalysts [37—40], harsh conditions, the use of large excess of thiols and necessitate anhydrous conditions to produce the desired products. Furthermore, these reagents cannot be recovered and recycled because they decompose or deactivate under quenching conditions. 

Good yields of p-aminosulfides have been obtained through the thiolysis of aziridines (Equation 44) [89]. The cleavage proved to be stereoselective as only the trans-diastereoisomers were formed. 

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