Iminophosphine Palladium Complexes in Catalytic Stille Coupling Reactions:  From Monomers to Dendrimers

Abstract

Palladium complexes of a variety of β- and γ-iminophosphines have been prepared and characterized by X-ray diffraction studies. Their properties as catalyst for three different Stille coupling reactions have been investigated and compared to catalytic performances of a phosphorus-containing dendrimer incorporating analogous γ-iminophosphine palladium complexes on the surface.

Synthesis and Core and Surface Reactivity of Phosphorus‐Based Dendrons

“…Indeed, we have shown previously that the corresponding Pd complexes linked to the surface of dendrimers efficiently catalyze Stille coupling reactions. [26] The palladium complex 15-G 2 is readily obtained by reaction with [PdCl 2 (COD)]. Here again the 31 P NMR spectrum gives very informative data for the characterization.…”

“…The numbering used for the NMR assignments is depicted in Figure 4. Compounds 2, [29] 4, [30] 7, [30] and 13 [26] were synthesized as reported previously. Phosphane 3-G 0 : A solution of (EtO) 2 P(O)CH 2 P(O)(OEt) 2 (0.500 g, 1.680 mmol) in THF (5 mL) was added to a suspension of NaH (0.043 g, 1.680 mmol) in THF (15 mL).…”

Cyclic β-iminophosphine: New P-stereogenic ligand for the asymmetric catalysed hydrogenation of ketones

“…Both enantiomers of the 16 electron complex 2 were prepared and isolated ex situ. The [1-(R P )]Ru(PPh 3 )Cl 2 and [1-(S P )]Ru(PPh 3 )Cl 2 were easily synthesized from Ru(PPh 3 ) 3 Cl 2 and the corresponding ␤-iminophosphine enantiomers (Scheme 2) [11].…”

“…Some of us developed a series of new P, N compounds and reported the synthesis of bi-and tricyclic ␤-iminophosphines [10] as well as the use of their palladium complexes in catalytic Stille coupling reactions [11]. Enantiopure derivatives were prepared in the case of the tricyclic ␤-iminophosphine 1.…”

Palladium immobilized in the nanocages of SBA-16: An efficient and recyclable catalyst for Suzuki coupling reaction

“…Palladium-catalyzed Suzuki coupling reaction has become the standard methodologies for the synthetic organic chemists to construct biarylunits [4][5][6]. Homogeneous palladium catalyst has been used in various coupling reactions such as Heck [7], Stille [8] and Suzuki [9], and provided high reaction rate or high turnover numbers (TON). However, the difficulty for the product separation and the problem for recycling of the catalyst have been the disadvantage of homogeneous catalyst and limited the application of homogeneous catalyst.…”