| Abstract
| - Cp*2TiMe2 has been found to be a competentcatalyst for the intermolecular addition of sterically lessdemanding n-alkyl- and benzylamines to internal alkynes.In the presence of 2.0−6.0 mol % of the catalyst, hydroamination reactions between n-propyl-, n-hexyl-, benzyl-, p-methoxybenzyl- or 2-phenylethylamine and diphenylacetylene, 3-hexyne or 4-octyne go to completion within 24 h orless at 114 °C (oil bath temperature). After subsequentreduction of the initially formed imines with zinc-modifiedsodium cyanoborohydride in MeOH at 25 °C, the corresponding secondary amines can be isolated in excellentyields (>78%). Hydroamination/reduction sequences employing the unsymmetrically substituted alkyne 1-phenylpropyne give access to mixtures of regioisomeric secondaryamines. The observed regioselectivity is low.
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