Phosphinates, arylation

The phosphine ligands suffer from P-C-bond cleavage, which result in the corporation of the phosphine aryl groups into an unwanted side product. This is due to the facile exchange of Ph and Ph Y between the Pd" centres and co-ordinated phosphines on an intermediates of type tranj-Pd(PPh,i)2(aryl)X ... 

Tertiary phosphines. Aryl triflates react with diary Ichlorophosphines by... 

New hybrid phosphine aryl and alkylphosphonate ligands (126) (Equation (31)) and (127), respectively, were prepared via transesterification with XSiMe3 (X = Br, Cl) and subsequent hydrolysis under mild conditions.249,250... 

Concerning the other a-donor /7t-acceptor phosphorus ligands, the low yields (5-21 %) are probably induced by a concurrent arylation of the phosphine destroying the starting complex during the reaction such phosphine arylations are already described in the literature (ref. 15) and phosphoniums salts were actually detected in the reaction mixture at the end of the reaction. 

Structural data obtained for the ort/jo-t-Pr-dppe-rhodium catalyst suggest restricted rotation of the phosphine aryl units, which is believed to be related to the latter outcome. 

A rather unexpected hydroxyphosphinylation of 3-cyclopropylideneprop-2-en-l-ones (343) with Ph3P and related phosphines, in which one of the phosphine aryl groups is lost, has been reported (Scheme 17). The reaction proceeds in acetone under aerobic... 

Copolymerization of ethene with norbomene and functionalized norbomenes in both non-aqueous and aqueous solutions could be carried out by (salicylaldimino) nickel methyl complexes [114,123-125], square-planar nickel complexes containing anionic P,0-chelates [126], and by Pd phosphine aryl sulfonates [127-129]. 

Figure 37 Structure of chelating bis-phosphine ligands accessible by modification of the phosphine aryl groups.

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