Poly phosphines

Examination of the backbones of the neopentane-based, carbon-anchored TIME and bulky TIME tripodal ligands reveals possible reasons for the lack of 1 1 complex formation with metal centers. A hypothetical complex of TIME would contain three eight-membered rings (Fig. 9, I) with much lower stability than the more commonly observed five, six, or seven-membered rings formed, for instance, by poly(p5irazolyl)borate or poly(phosphine) ligands. In order... 

CC Poly (phosphine oxide) Proban CC polymer Rhodia... 

The synthesis of poly phosphine macrocycles requires the joining of a bidentate phosphine with other donor ligands via an alkyl or aryl chain. The synthesis of... 

Linear carbodiimides with pendant carbodiimide groups are obtained by reacting polymeric azides derived from vinyl azide 33 with triphenylphosphine to form poly(phosphine imines) 34, which are subsequently converted to polycarbodiimides 35." ... 

This paper describes the electrophilic ring-opening polymerization of seven new cyclic phosphorus(III) compounds, 1-7. The polymerization of five- and slx-membered deoxophostones, 1 and and of a benzoxaphosphole 2, produced poly (phosphine oxldejs 11, and via Arbuzov type reactions. The polymerization of f e and slx-" membered deoxothlolphostones, 4 and 5, gave poly(phosphine... 

Five- and slx-membered deoxothlolphostone ( and have been obtained as new compounds Then P NMR signals are observed at +22 ppm ( ) and at +5 ppm ( (26). The ring-opening polymerizations of and when Induced by a cationic Initiator give rise to white powdery materials of poly(phosphine sulflde)s and (Table VI) (27). The structures of and have been demonstrated by... 

In addition to the bidentate ligands depicted in Table 6.15, there are tripod-type ligands (below) and many other multidentate poly(phosphine) ligands which can form complexes. Those based on phenyl groups seem to be the most popular (Chapter 6.17). Poly(phosphine) ligands are useful in stabilising metal cluster complexes (above) and cyclic and acyclic P units. 

When carbon chain poly(phosphines) act as multidentate ligands they form chelate rings containing carbon, phosphorus and a metal atom. They can be made by reactions analogous to those employed for monodentate derivatives above. In reaction (8.137) a linear complex is first formed, but on raising the temperature a cyclic derivative is obtained. 

Polyphosphine (polyphosphane) complexes were first discovered in 1958 when Burg and Mahler [5] made the diphosphine (8.229). By 1990 over 500 diphosphine (diphosphane) complexes had been synthesised as well as a number of poly-phosphine complexes. 

These polymerizations proceed mostly by a Michaelis-Arbuzov (M-A) type of rearrangement (Scheme 1), involving cyclic phosphonium intermediates to produce poly-phosphinates or polyphosphonates (39). The presence of isomerized repeating units (40) was the result of the occurrence of side reactions. Sometimes the proportion of the isomerized units was higher than that of the normal units (39). ... 

Polymer with the prevailing stmcture of poly(phosphine oxide) (poly-49 Mn = 3.9 x 10 ) was obtained in the cationic polymerization of 2-phenyl-1,2-oxaphospholane (49). Poly-49 was next reduced to the corresponding polyphosphine to confirm its stmcture. Stmcture 49 was also polymerized with chloro-and/or iodomethylated polystyrene, giving graft copolymers. 

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