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A friend of mine, final year PhD, and I, final year Bachelor, are focusing on hydroamination reactions. In particular those with secondary amines and substituted alkenes. The reaction in particular is given by

enter image description here

Intermolecular hydroamination of unactivated alkenes with substituted secondary amines seems to be quite difficult. However, additions of cyclic and acyclic secondary alkyl amines to a wide range of alkenes with anti-Markovnikov regioselectivity have been reported. Some of those reactions are redox-neutral and occur readily at room temperature under visible light irradiation.

Our question is: what would be an applicable catalyst for this particular reaction (secondary amine + substituted alkene) and what reaction conditions would be necessary?

Thanks in advance!

EDIT:

The reaction may also concerns the primary amine,

enter image description here

However, we would like to keep the substituted alkene substrate as it is.

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  • $\begingroup$ I think converting to tertiary halide and then reacting it with secondary amine, while sort of primitive, may be more effective method in this case. $\endgroup$ – Mithoron Apr 9 at 0:47
  • $\begingroup$ Have you tried looking in the literature? $\endgroup$ – Zhe Apr 12 at 13:40
  • $\begingroup$ @Zhe Yes have, the problem we face however is the second methyl group that forms (resulting from the alkene substrate). It causes problems with hydrogen abstraction in certain mechanisms. $\endgroup$ – Jameson Apr 12 at 22:27
  • $\begingroup$ @Zhe by this I mean the two methyl groups next to each nitrogen $\endgroup$ – Jameson Apr 12 at 23:34
  • $\begingroup$ Why not methylate after? $\endgroup$ – Zhe Apr 13 at 2:41
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You may follow the procedure in this reference. I included the abstract for your convenience:

Abstract: The hydroamination of styrene with aniline catalyzed by phosphine-ligated palladium triflates exhibits a substantial $\ce{^{13}C}$ isotope effect at the benzylic carbon. This supports rate-determining nucleophilic attack of amine on a $\eta^3$-phenethyl palladium complex. Deuterium exchange observations and predicted isotope effects based on DFT calculations support this mechanism. Selectivity in these reactions is determined by the facility of palladium displacement after reversible hydropalladation of the alkene.

The Graphical Abstract:

Hydroamination reaction

Reference:

L. K. Vo, D. A. Singleton, “Isotope Effects and the Nature of Stereo- and Regioselectivity in Hydroaminations of Vinylarenes Catalyzed by Palladium(II)−Diphosphine Complexes,” Org. Lett. 2004, 6(14), 2469–2472 (DOI: 10.1021/ol049137a).

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