Technology Spotlights DalPhos Ligands

Professor Mark Stradiotto and coworkers at Dalhousie University have developed air-stable Dalphos, which contains the bulky di(1-adamantyl)phosphino [P(1-Ad)₂] fragment. These chelating N,P ligands are useful for previously unprecedented Pd-catalyzed C-N and C-C bond formation. Both Me-DalPhos (Cat. No. 751413) and Mor-DalPhos (Cat. No. 751618) allow for Pd-catalyzed ammonia cross-coupling. In particular, the more reactive Mor-Dalphos improved the scope and utility of ammonia coupling at room temperature.

Cat. No. 751618

Cat. No. 751413

Benefits of DalPhos Ligands:

• Monoarylation of ammonia, hydrazine and acetone
• Air-stable
• Good functional group tolerance
• Mild conditions

Me-DalPhos featuring an ortho-dimethylamino group has been shown to be a valuable ligand for the Pd-catalyzed cross-coupling of aryl chlorides and amines (including ammonia). The highly efficient Mor-Dalphos, where the dimethylamino group is replaced by morpholine, easily enables the ammonia coupling of a range of aryl chlorides and aryl tosylates.

Cross-Coupling of Ammonia

Mor-DalPhos can be used for the first Pd-catalyzed cross-coupling of aryl chlorides and tosylates with hydrazine. The Stradiotto group also explored the scope of the reaction of aryl hydrazines with benzaldehydes to afford the corresponding aryl hydrazones.

Cross-Coupling of Hydrazine

The direct arylation of acetone with a range of aryl halides and tosylates has been reported with good monoarylation selectivity. The use of Mor-DalPhos has a key impact on the rate and selectivity of this reaction.

Cross-Coupling of Acetone

The use of Mor-DalPhos for the gold-catalyzed hydroamination of internal aryl alkynes with dialkylamines has been studied. This gold precatalyst featuring a P,N-ligand effects the stereoselective addition of a variety of functionalized dialkylamines to unsymmetrical internal arylacetylenes.

Gold-Catalyzed Hydroamination

References:

1.  Lundgren, R. J.; Peters, B. D.; Alsabeh, P. G.; Stradiotto, M. Angew. Chem. Int. Ed . 2010, 49, 4071.
2.  Lundgren, R. J.; Stradiotto, M. Angew. Chem. Int. Ed. 2010, 49, 8686.
3.  Hesp, K. D.; Lundgren, R. J.; Stradiotto, M. J. Am. Chem. Soc. 2011, 133, 5194.
4.  Lundgren, R. J.; Sappong-Kumankumah, A.; Stradiotto, M. AChem. Eur. J. 2010, 16, 1983.
5.  Hesp, K. D.; Stradiotto, M. J. Am. Chem. Soc. 2010, 132, 18026.

Watch Professor Stradiotto’s presentation at Aldrich.com/aldwebinar

Product Information

751618 Di(1-adamantyl)-2-morpholinophenylphosphine (Mor-DalPhos)

751413 Di(1-adamantyl)-2-dimethylaminophenylphosphine (Me-Dalphos)