75934-30-4Relevant academic research and scientific papers
Simple, efficient catalyst system for the palladium-catalyzed amination of aryl chlorides, bromides, and triflates
Wolfe, John P.,Tomori, Hiroshi,Sadighi, Joseph P.,Yin, Jingjun,Buchwald, Stephen L.
, p. 1158 - 1174 (2007/10/03)
Palladium complexes supported by (o-biphenyl)P(t-Bu)2 (3) or (o- biphenyl)PCy2 (4) are efficient catalysts for the catalytic amination of a wide variety of aryl halides and triflates. Use of ligand 3 allows for the room-temperature catalytic amination of many aryl chloride, bromide, and triflate substrates, while ligand 4 is effective for the amination of functionalized substrates or reactions of acyclic secondary amines. The catalysts perform well for a large number of different substrate combinations at 80-110 °C, including chloropyridines and functionalized aryl halides and triflates using 0.5-1.0 mol % Pd; some reactions proceed efficiently at low catalyst levels (0.05 mol % Pd). These ligands are effective for almost all substrate combinations that have been previously reported with various other ligands, and they represent the most generally effective catalyst system reported to date. Ligands 3 and 4 are air-stable, crystalline solids that are commercially available. Their effectiveness is believed to be due to a combination of steric and electronic properties that promote oxidative addition, Pd-N bond formation, and reductive elimination.
SYNTHESIS OF INDOLES FROM N-(TRIFLUOROACETYL)-2-ANILINO ACETALS
Nordlander, J. Eric,Catalane, David B.,Kotian, Kirtivan D.,Stevens, Randall M.,Haky, Jerome E.
, p. 778 - 782 (2007/10/02)
N-(trifluoroacetyl)indoles (3) are produced in high yield from appropriately ring-substituted N-(trifluoroacetyl)-2-anilino acetals (2) in boiling trifluoroacetic acid containing excess trifluoroacetic anhydride.Mild saponification provides the free indoles nearly quantitatively.The scope of the reaction is discussed.The ring closure follows solvolytic substitution of a trifluoroacetoxy group for one of the ethoxy groups in 2.The method has been extended to cyclization of N-(trifluoroacetyl)-α-anilinoacetone in hot polyphosphoric acid followed by saponification to yield 3-methylindole.
