Ligands iminophosphine

Williams, D.B.G., Traut, T, Kriel, F.H. and van Zyl, W.E. (2007) Bidentate amino-and iminophosphine ligands in mono-and dinuclear gold(I) complexes Synthesis, structures and AuCl displacement by AuC E . Inorganic Chemistry Communications, 10(5), 538-542. 

Biaryls and 1,3-dienes can be synthesized by the Pd-promoted oxidative homocoupling of different substrates. The homocoupling of the arylstannane 172 and the alkenylstannane 175 gives the biaryl 173 and 1,3-diene 176 using a catalytic amount of Pd(OAc)2 and 02 in the presence of the iminophosphine ligand 174, or in the absence of ligand [107a]. 

Hiyama has used the ingenious sttategy of inttamolecular activation to facilitate the cross-coupling of readily accessible and stable silanes with aryl iodides (Equation 109) <2005JA6952>. The thienylsilane 223 could be reacted with ethyl 4-iodobenzoate in the presence of PdCl2 and the iminophosphine ligand 224 to give the product in 93% yield. 

Scheme 5 Synthesis of iminophosphine ligands by Schiff base condensation...

SYNTHESIS AND APPLICATION IN PALLADIUM-CATALYSED ASYMMETRIC ALLYLIC SUBSTITUTION OF ENANTIOPURE CYCLIC p-IMINOPHOSPHINE LIGANDS... 

Asymmetric palladium(0)-catalysed substitution of racemic allylic substrates with malonate and benzylamine as nucleophiles were performed using new enantiopure cyclic (3-iminophosphine ligands namely (2,6-dimethyl-phenyl)-( 1 -phenyl-2, 3,3a, 8a-tetrahydro- 1H-1 -phospha-cyclopenta[-a]inden-8-ylidene)-amines 1 (RP)... 

A convenient catalyst system, consisting of [Pd(OAc)2] and PPhs in dimethyl-sulfoxide (DMSO) as solvent and K3PO4 as base was recently reported [14], and found to be effective for the coupling of aryl halides with terminal alkynes. Among various ligands tested, an iminophosphine ligand gave (in some cases) better conversions than when PPhs was employed. 

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