Issue Date: February 9, 2009
Organoactinide Hydrothiolation Catalysts
Vinyl sulfides can be made selectively and in high yield by adding thiols to terminal alkynes in the presence of organoactinide catalysts, according to a new study (J. Am. Chem. Soc., DOI: 10.1021/ja808764q). That transformation—hydrothiolation—provides a synthetic route for preparing valuable sulfur-containing compounds such as pharmaceuticals, natural products, and chemical reagents. Other hydrothiolation procedures are available, but those methods are ineffective at converting aliphatic thiols. In addition, those methods yield only the anti-Markovnikov addition product—the reaction product formed by adding hydrogen to the least protonated unsaturated carbon. Charles J. Weiss, Stephen D. Wobser, and Tobin J. Marks of Northwestern University have developed thorium(IV)- and uranium(IV)-cyclopentadienyl-based catalysts that hydrothiolate a broad range of alkyl, aryl, and vinyl alkynes with aliphatic, aromatic, and benzylic thiols. For example, 1-pentanethiol and 1-hexyne react via Markovnikov addition to form the corresponding vinyl sulfide with a yield and selectivity of roughly 100%. The team is now investigating the reaction mechanism to uncover the basis of the high regioselectivity.
- Chemical & Engineering News
- ISSN 0009-2347
- Copyright © American Chemical Society