Synthesis continued phosphonium salt

Preparation. - A range of 1,3-dithianylphosphonium salts (218) has been prepared in the course of further studies of sulfur lone pair anomeric effects in these systems.Conventional quatemization reactions have been used in the synthesis of the salt (219) and a range of polymer-supported phosphonium salts (220). A new efficient route to salts of the type (221) has been developed. The of>-azolylalkylphosphonium salts (222) are readily accessible from the reactions of the corresponding a>-bromoalkylphosphonium salts and azoles. Routes to vinylphosphonium salts, e.g., (223), continue to be explored, and their reactivity utilised in the synthesis of phosphonium salts bearing heterocyclic substituents, e.g., (224). The betaine (225) has been... 

Phosphines (continued) oxides, 32 366-367 synthesis of, 25 94 as probe molecules, 42 170,172 (Phosphinoalkyl)phosphonium salts, 42 480 Phosphobetaine, 25 88... 

Tundo, P. and Selva, M. (2005). Continuous-flow, gas phase synthesis of 1-chlorobutane (1-bromobutane) from 1-butanol and aqueous HCl (HBr) over silica-supported quaternary phosphonium salt. Green Chem., 7,464-467. 

Reactions of acyclic phosphazenes continue to prove of value in the synthesis of new materials especially in the area of organic chemistry. Reactions in which the phosphazene unit is transformed will be considered first followed by reactions in which the phosphazene unit stays intact. The phosphazenes are usually prepared by the Staudinger reaction. The diversity of reactivity of phosphazenes such as PhN=PPh2CH=C(NH2)C H -p-Me in interactions with electrophiles is shown by reactions with protons or alkyl halides which give phosphonium salts (N-alkylation or protonation). presence of bases, alkylation of the enamlne occurs. 

Interest in the chemistry of phosphines and phosphonium salts continues at a high level, and, as in previous years, considerable selection has been necessary in the preparation of this Report. A noticeable feature has been the large number of papers concerned with the preparation of chiral phosphines and their use in the homogeneous catalysis of asymmetric synthesis. Of these, only those involving some new aspect of organophosphorus chemistry are included here. 

Interest in the synthesis and reactivity of the six-membered, potentially aromatic, phosphinine ring system has also continued, but at a much lower level than in recent years. New synthetic work includes the application of the pyrylium salt route to phosphinine synthesis, this time starting from pyrylium salts bearing chiral substituents to give the related chiral phosphinines," and the development of new routes to the 2-phosphanaphthalene (137)" ° and the phosphinine-2-aldehyde (138). Also reported is an approach to the synthesis of l,2-dihydro-l,4,2-benzo-diazaphosphinines," cationic gold(I) complexes of 2,4,6-tri-t-butyl-l,3,5-triphosphabenzene," and the synthesis of some X -phosphinines from phosphonium-iodonium ylides." " ... 

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