A New Efficient Palladium Catalyst for the Amination of Aryl Chlorides

Abstract

A highly active catalyst for the Buchwald-Hartwig ­amination has been developed. The new catalyst, a combination of a dimethylaminomethyl ferrocene palladacycle and bis(2-norbornyl)phosphine shows high activity and broad scope for the ­coupling of non- or deactivated aryl chlorides with primary and secondary amines as well as (hindered) anilines.

Key words

Buchwald-Hartwig amination - aryl chloride - Pd cata­lysis - palladacycle - secondary phosphine - SK-CC02-A

References

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7

Available from Strem and Fluka or in technical quantities from Solvias.

8

For a related single-component catalyst see ref. 4d.

11

Typical Procedure: The catalysts were prepared by mixing the secondary phosphine with the Pd precursor (1:1 ratio) in dioxane at r.t. for 30 min. Then, 1 mmol Ar-Cl and 1.2 mmol amine were added to the reaction tubes containing 2.5 mL dioxane 1.4 mmol NaOt-Bu and dodecane (internal standard). The mixture was heated to 80 °C, 0.5 mL catalyst solution (0.005 mmol Pd) was added and then heated further to 110 °C where the reaction was performed. After 2 h samples were taken and analyzed by GC.

15

For detailed comparisons see: product P2, ref. 4c,4d; product P3, ref. 5b; product P4, ref. 4a, 5b; product P5, ref. 5a; product P8, ref. 4a, 4c, 4d, 5a.

16

The single experiments were performed on a 1 mmol scale in analogy to ref. 12.