868666-47-1Relevant academic research and scientific papers
Anti-Markovnikov hydroamination of terminal alkynes
Tillack, Annegret,Garcia Castro, Ivette,Hartung, Christian G.,Beller, Matthias
, p. 2541 - 2543 (2002)
Titanocene-η-alkyne complexes such as 1 are efficient catalysts for the hydro-amination of terminal alkynes to imines (see scheme; R = alkyl, R′ = SiMe3 or Ph). Excellent yields of imines and good to excellent regioselectivities for the anti-Markovnikov products were obtained.
Hydroamination/hydrosilylation sequence catalyzed by titanium complexes
Heutling, Andreas,Pohlki, Frauke,Bytschkov, Igor,Doye, Sven
, p. 2951 - 2954 (2007/10/03)
(Chemical Equation Presented) A single precatalyst is used for the sequential combination of the Ti-catalyzed hydroamination of alkynes with the Ti-catalyzed hydrosilylation of imines. In this way alkynes and primary amines are converted efficiently into
[Ind2TiMe2]: A general catalyst for the intermolecular hydroamination of alkynes
Heutling, Andreas,Pohlki, Frauke,Doye, Sven
, p. 3059 - 3071 (2007/10/03)
[Ind2TiMe2] (Ind=indenyl) is a highly active and general catalyst for the intermolecular hydroamination of alkynes. It catalyzes the reaction of primary aryl-, tert-alkyl-, sec-alkyl-, and nalkylamines with internal and terminal alkynes. In the case of unsymmetrically substituted 1-phenyl-2-alkylalkynes, the reactions occur with modest to excellent regioselectivities, whereby formation of the anti-Markovnikov regioisomers is favored. While the major product of hydroamination reactions of terminal arylalkynes is always the anti-Markovnikov isomer, alkylalkynes react with arylamines to preferably give the Markovnikov products. To achieve reasonable rates for the addition of sterically less hindered n-alkyland benzylamines to alkynes, these amines must be added slowly to the reaction mixtures. This behavior is explained by the fact that the catalytic cycle proposed on the basis of an initial kinetic investigation includes the possibility that the rate of the reaction increases with decreasing concentration of the employed amine. Furthermore, no dimerization of the catalytically active imido complex is observed in the hydroamination of 1-phenylpropyne with 4-methylaniline in the presence of [Ind2TiMe2] as catalyst. In general, a combination of [Ind2TiMe2]-catalyzed hydroamination of alkynes with subsequent reduction leads to the formation of secondary amines with good to excellent yields. Particularly impressive is that [Ind 2TiMe2] makes it possible for the first time to perform the reactions of n-alkyl- and benzylamines with 1-phenylpropyne in a highly regioselective fashion.
