Ruthenium-catalyzed stereoselective anti-Markovnikov-addition of thioamides to alkynes.
A catalyst system generated in situ from bis(2-methallyl)-cycloocta-1,5-diene-ruthenium(II) and a phosphine was found to efficiently catalyze the addition of thioamides to terminal alkynes with exclusive formation of the anti-Markovnikov thioenamide products. The stereoselectivity of the addition is usually high and controlled by the choice of the phosphine ligand, whereas the (E)-isomers are predominantly formed in the presence of tri(n-octyl)phosphine, the use of bis(dicyclohexylphosphino)methane preferentially leads to the formation of the (Z)-configured thioenamides.
Goossen
Lukas J
LJ
Fachbereich Chemie, TU Kaiserslautern, Erwin-Schrödinger-Strasse, Building 54, D-67663 Kaiserslautern, Germany. goossen@chemie.uni-kl.de
Blanchot
Mathieu
M
Salih
Kifah S M
KS
Karch
Ralf
R
Rivas-Nass
Andreas
A
D000480:Alkynes / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D015394:Molecular Structure; D012428:Ruthenium / Q000737:chemistry*; D013237:Stereoisomerism; D013438:Sulfhydryl Compounds / Q000737:chemistry; D013854:Thioamides / Q000737:chemistry*
D000480:Alkynes; D013438:Sulfhydryl Compounds; D013854:Thioamides; D012428:Ruthenium