Sonogashira coupling of functionalized trifloyl oxazoles and thiazoles with terminal alkynes: synthesis of disubstituted heterocycles.
[reaction: see text] This paper describes Sonogashira cross-coupling of functionalized 2-, 4-, and 5-trifloyl oxazoles and thiazoles with terminal alkynes. This methodology has been extended to 2,4-ditrifloylthiazoles, which results in regioselective cross-coupling at the C2-position of the thiazole. The resulting 2-alkynyl-4-trifloylthiazoles are effective electrophiles in a second palladium(0)-mediated cross-coupling reaction.
Langille
Neil F
NF
Department of Chemistry and Center for Streamlined Synthesis, Metcalf Center for Science and Engineering, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, USA.
Dakin
Les A
LA
Panek
James S
JS
D000480:Alkynes / Q000737:chemistry*; D002384:Catalysis; D002626:Chemistry, Pharmaceutical / Q000379:methods; D006571:Heterocyclic Compounds / Q000138:chemical synthesis*; D010080:Oxazoles / Q000737:chemistry; D010165:Palladium / Q000737:chemistry; D013844:Thiazoles / Q000737:chemistry
D000480:Alkynes; D006571:Heterocyclic Compounds; D010080:Oxazoles; D013844:Thiazoles; D010165:Palladium