Synthesis of Isotopically-Labeled 1,3-Dithiane

Synthesis of Isotopically-Labeled 1,3-Dithiane

The reagent 1,3-dithiane has been a very useful synthon for the production of aldehydes and ketones.  It is normally produced by the reaction of formaldehyde or its diethyl acetal with 1,3-propanedithiol.  The reported yields for these reactions are about 85%. 

We wanted to produce isotopically-labeled dithiane from a single source.  We have used [¹³C]methyl phenyl sulfoxide to accomplish our goal. The [¹³C]methyl phenyl sulfoxide can be treated with trifluoroacetic anhydride to give the Pummerer product which is then treated with 1,3-propanedithiol to give isotopically-labeled 1,3-dithiane.  This represents the first synthesis of isotopically-labeled 1,3-dithiane.  An additional advantage to the use of [¹³C]methyl phenyl sulfoxide for the production of 1,3-dithiane is that the deuterated isotopomer can also easily be produced as is shown below. 

The details of this work will be presented.