Phosphonyl group

Recently, Fossum et al. prepared several phosphine-oxide-containing monomers (Scheme 6.23).163 These monomers were used to prepare hyperbranched polymers in a typical aromatic nucleophilic substitution. However, only oligomers with M lower than 2500 g/mol were obtained. These results did not surprise us, since our previous work demonstrated that the para-hydroxyl group of the phosphonyl group is not very reactive and would require higher reaction temperatures.11... 

Phosphonoformic acid (85) decarboxylated in acid solution, and it was proposed that the uncatalysed reaction involved a simple decarboxylation of the zwitterion. The acid-catalysed reaction showed some kinetic similarity to that of mesitoic acid and an elimination of carbon dioxide as trihydroxymethylcarbonium ion was preferred. Participation of the trans vicinal phosphonyl group in the solvolysis of the halides (86) and (87) has been deduced from rate measurements. In the norbornene derivatives, the relative rates of loss of chloride from (87a) and (87b) were 5 x 10 1. 

III. Monosaccharides Having a Phosphonyl Group in the Furanose Ring. 176... 

II. Monosaccharides Having a Phosphinediyl or Phosphonyl Group in the Pyranose Ring... 

Nucleophilic Substitution in a-Position 3.2.4 Reactions of the Phosphonyl Group References... 

Aminocarboxylation (Strecker and Related Reactions) 5.2.8 Reactions of the Phosphonyl Group Dealkylation... 

Generally, the phosphonyl group is installed using carbanion-based chemistry. Methods for introducing the phosphonate group as part of a one-, ° three-,or four-carbon fragment have been described.- - In the C-1 case, stabilized (Z = or nonstabilized... 

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