293313-60-7Relevant academic research and scientific papers
Silver-catalyzed intermolecular hydroamination of alkenes and 1,3-dienes
Giner, Xavier,Najera, Carmen
, p. 3211 - 3213 (2009)
Silver triflate is used as efficient catalyst for the intermolecular addition of 4-toluenesulfonamide to alkenes under thermal or microwave heating. The hydroamination of 1,3-dienes can be performed at 85 °C with low catalyst loading (0.1-5 mol%) or at room temperature using 1 mol% of AgOTf, the use of HOTf affording similar results.
Gold versus silver-catalyzed intermolecular hydroaminations of alkenes and dienes
Giner, Xavier,Najera, Carmen,Kovacs, Gabor,Lledos, Agusti,Ujaque, Gregori
experimental part, p. 3451 - 3466 (2012/02/04)
Comparative studies about the hydroamination of unactivated alkenes and dienes catalyzed by either cationic gold(I) triphenyl phosphite complexes or silver salts were performed using sulfonamides, anilines and carbamates as nucleophiles. Gold-catalyzed reactions generally, need lower loadings than those carried out with silver salts. Simple alkenes react only with sulfonamides and weak aromatic amines such as p-nitroaniline, whereas for conjugated dienes carbamates can also be used. Carbon-carbon double bond isomerization is observed only with gold similarly to when triflic acid was used, affording mixtures of regioisomeric products in the same cases. Silver-catalyzed hydroaminations failed with terminal alkenes, except with styrenes. Conjugate dienes can be hydroaminated either at 85 °C in toluene or at room temperature in dichloromethane. Non-conjugated 1,4- and 1,5-dienes suffer double hydroamination leading to saturated N-tosylated heterocyclic amines The catalytic cycle for the silver(I)-catalyzed hydroamination process has been computationally analyzed, resembling gold(I)-catalyzed processes, although with some significant differences. Copyright
(Alkylthio)alkynes as addends in the Co(0) catalyzed intramolecular pauson-khand reaction. Substituent driven enhancements of annulation efficiency and stereoselectivity
Pagenkopf, Brian L.,Belanger, David B.,O'Mahony, Donogh J. R.,Livinghouse, Tom
, p. 1009 - 1019 (2007/10/03)
Compared to terminal alkynes, (methylthio)alkynes are generally superior substrates for the thermally promoted, Co2(CO)8 catalyzed Pauson-Khand reaction of enynes and allenynes, providing enones in higher yields and with enhanced diastereoselectivity. Improvements in yield dependent upon the use of 2,2,2-trifluoroethanol as co-solvent and an apparent preference for endo selectivity with (ethoxy)alkynes are also disclosed.
