DBU‐Mediated Intermolecular 5‐exo‐dig Cyclization of PropargylAlcohols and Carbon Disulfide to [1,3]‐Oxathiole‐2‐thiones

Abstract

5‐exo‐dig is a versatile Baldwin tool to predict and make useful heterocyclic compounds from nucleophiles and electrophiles. In order to aid this, a novel metal‐free method is proposed to produce [1,3]‐oxathiole‐2‐thiones from a readily synthesized propargyl alcohols and easily accessible carbon disulfide, where both secondary and primary propargyl alcohols are compatible to this methodology. This procedure is simple, versatile, atom economy and functional group tolerance resulting in moderate to excellent yields. Finally, the process was screened on different mode of reaction operation.

Synthesis of Cyclic Trithiocarbonates from Carbon Disulfide and Propargyl Alcohols under Mild Conditions

“…Based on an extensive series of experiments informed by the literature, along with controlled experiments, we have proposed a plausible mechanism (Scheme ). Initially, DBN deprotonates the hydroxyl group of 1a , leading to the corresponding anion attacking the carbon of CS 2 . Subsequently, the sulfur anion of CS 2 attacks the carbon of CS 2 , forming intermediate D .…”