The Versatility of α-Chloropropargyl Phenyl Sulfide Affords High Stereo- and Regioselectivities in Indium-Promoted Coupling Reactions under Mild Conditions

• Published in: Journal of organic chemistry Vol. 67; no. 1; pp. 136 - 145
• Main Authors: Mitzel, Thomas M, Palomo, Carolyn, Jendza, Keith
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 11.01.2002; Amer Chemical Soc
• Subjects: Chemistry; Chemistry, Organic; Exact sciences and technology; Noncondensed benzenic compounds; Organic chemistry; Physical Sciences; Preparations and properties; Science & Technology; CHLOROSULFIDES; DIASTEREOSELECTION; BROMODIFLUOROMETHYLACETYLENE DERIVATIVES; AQUEOUS-MEDIA; ALLYLATION; ALDEHYDES; 1,2-ADDITION; SOLVENT SYSTEMS; SELECTIVITY; BETA; Acetylenic compound; Regioselectivity; Propargylic compound; Three membered ring; Aldehyde; Oxygen heterocycle; Indium; Chemical coupling; Stereoselectivity; Cyclization; Chlorine Organic compounds; Epoxide; Chelation; Indium III Chlorides; Chemical synthesis
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/jo015992l

Coupling reactions between α-chloropropargyl phenyl sulfide (11) and a series of aldehydes under aqueous conditions are reported. Not only is good stereoselectivity observed between syn and anti isomeric products, but excellent regioselectivity is also witnessed. In reactions using indium metal as a promoter, the propargyl functionality (12) is retained, unlike the use of more traditional metals that result in formation of products containing a mixture of both propargyl (12) and allene (13) moieties. The reaction is postulated to proceed via either a chelated or nonchelated route, controlled by the presence or absence of indium (III) chloride, and may be used to create synthetically useful building blocks. The formation of epoxyalkyne (14) molecules, which are found in many natural products and have wide use as synthetic templates, is presented as one example.