Cross-coupling with organoboron compounds

Palladium-catalyzed cross-coupling with organoboron compounds... 

Cross-coupling with organoboron compounds (the Suzuki-Miyaura reaction) is by far the most popular and versatile method of cross-coupling, and has been extensively reviewed.3-5... 

D.iii.b. Aqueous Phosphine-Free Method. The use of palladium catalysts without the addition of phosphine ligands for cross-coupling with organoboron compounds in aqueous media allows a dramatic increase in catalyst efficiency, with the reaction being performed under milder conditions. 

As alternatives to the use of organic electrophiles, hypervalent iodonium com-poundst" and organolead compounds have been employed in cross-coupling with organoboron compounds. 

It should be noted that cross-coupling in the presence of phosphine complexes of palladium usually requires high amounts of catalyst, with initial loadings of 25-30 mol% not being uncommon. An entirely new approach to the Suzuki reaction is phosphine-free palladium catalysis. The use of palladium catalysts without the addition of phosphine ligands for cross-coupling with organoboron compounds in aqueous media opened a new chapter in the story of this powerful synthetic method. This approach allows catalyst efficiency to be dramatically increased, and the reaction to be performed under milder conditions. 

Jang, S.-B, Polymer-Bound Palladium-Catalysed Cross-coupling of Organoboron Compounds with Organic Halides and Organic Triflates, Tetrahedron Lett. 1997, 38, 1793-1796. 

Jang SB, Polymer-bound palladium-catalyzed cross-coupling of organoboron compounds with organic halides and organic triflates, Tetrahedron Lett., 38 1793-1796, 1997. 

Cross-coupling of Organoboron Compounds with Organic Halides... 

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