Buchwald-Hartwig cross-coupling

The first step in the catalytic cycle is the oxidative addition of Pd to the aryl halide (or sulfonate). In the second step 

In the laboratory of G.A. Sulikowski, an enantioselective synthesis of a 1,2-aziridinomitosene, a key substructure of the mitomycin antitumor antibiotics, was developed. Key transformations in the synthesis involved the Buchwald-Hartwig cross-coupling and chemoselective intramolecular carbon-hydrogen metal-carbenoid insertion reaction. 

Naturally occurring phenazines have interesting biological activities but the available methods for their preparation offer only poor yields. T. Kamikawa et al. prepared polysubstituted phenazines by a new route involving two subsequent Pcf -catalyzed amlnations of aryl bromides using the conditions developed by Buchwald and Hartwig.  

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The Chan-Lam Coupling may be conducted at room temperature in air, which gives it a certain advantage over the Buchwald-Hartwig Cross Coupling. 

Pd-catalyzed Buchwald-Hartwig cross-coupling Direct Pd-catalyzed C-N and C-O bond formation between aryl halides and amines or alcohols. 70... 

Related reactions Buchwald-Hartwig cross coupling ... 

Nucleophilic aromatic substitution reactions were employed to place amines on pyrimidine and pyrimidinone rings. As a more economical substitute for Buchwald-Hartwig cross-coupling reaction conditions GeUis and collaborators developed a DMAP-catalyzed, microwave-assisted method to form 4-hetero-arylamino-substituted quinazolines (Scheme 33) (14T8257). Treatment of... 

Hartwig (see Buchwald-Hartwig Cross Coupling Reaction)... 

Typical Buchwald-Hartwig Cross-Coupling Procedure. Synthesis of N,N-Diethyl-N-phenylanthranilamide 1124 Acknowledgments 1124... 

Preprepared (ADC)Pd complexes H2 (Fig. 11.6) was employed [29] as catalyst for the Buchwald-Hartwig amination of aryl halides (for the recent surveys on the Buchwald-Hartwig cross-coupling, see References [62-65]). The obtained results (Scheme 11.13) were compared with those for the structurally related oxyamino- (H4), thioaminocarbene (H5), and the related NHC complex, H14. Catalysts H2, H4, and H5 were efficient in the amination of bromobenzene (yields range from 82% to 92%), demonstrating activities similar to those of the NHC complex H14 (yield 84%). With 2-chloropyridine as the substrate, H2, H4, and H14, allowed the preparation of the target product in a quantitative yield. Catalyst H5 demonstrated a moderate efficiency (yield 47%). 

Jin, X. Uttamapinant, C. Ting, A. Y. Synthesis of 7-aminocoumarin by Buchwald-Hartwig cross coupling for specific protein labeling in living cells. ChemBioChem 2011,12, 65-70. 

Although one of the more recent additions to the armamentarium of these palladium-catalysed reactions, the Buchwald-Hartwig cross-coupling of amines with aiyl halides already has found applications in macrocycle synthesis. In the first example, Iqbal et al used this coupling as the cyclization step in the synthesis of constrained tri- or tetra-peptidomimetics with a biaiyl linker (Scheme 11.13 illustrates a tripeptidomimetic (112)). Fair to moderate yields were obtained for products containing 16- to 22-membered rings. 

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