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Phosphites trialkylphosphites

Trialkyl esters of phosphonic acid exist ia two structurally isomeric forms. The trialkylphosphites, P(OR)2, are isomers of the more stable phosphonates, 0=PR(0R)2, and the former may be rearranged to resemble the latter with catalytic quantities of alkylating agent. The dialkyl alkylphosphonates are used as flame retardants, plasticizers, and iatermediates. The MichaeUs-Arbusov reaction may be used for a variety of compound types, including mono- and diphosphites having aryl as weU as alkyl substituents (22). Triaryl phosphites do not readily undergo the MichaeUs-Arbusov reaction, although there are a few special cases. [Pg.375]

A study of sequential Arbuzov-type demethylation reactions of the platinum(II)-phosphite complex [Pt P(OMe)3 4]2+, in which the phosphite ligands are converted to phosphonates, has been described.285 Many of the products of the reaction were characterized by NMR spectroscopy and X-ray crystallography.286 The X-ray structures are the first reported for trialkylphosphite complexes of platinum(II). [Pg.708]

Formation of P=N-P-Bridges. A simple reliable synthesis of N-phosphorylated phosphazenes which avoid the handling of the dangerous phosphoryl azides consists in a direct reaction of di- and trialkyl-phosphites and carbon tetrachloride with sodium azide in a single step procedure (eq. 11). The phosphoryl azides formed intermediately instantly react with the trialkylphosphites present. Therefore, their... [Pg.299]

The reaction of l,3-dichalcogeno-2-selones with trialkyl phosphites has been used to synthesize perchalcogenofulvalenes, although the yields of the products are moderate (Eq. 24) [16,87]. On the other hand, the treatment of selenothioic acid S-esters and diselenoesters with trialkylphosphites gives phosphoryl sulfides and selenides in good yields (Eq. 25) [88]. [Pg.189]

Tervalent phosphorus compounds (phosphorous derivatives) are weil-established reagents for the deoxygenation of amine oxides and nitrones, and they provide a clean and convenient method for the preparation of furazans from furoxans. Mukaiyama et al.425 and Grundmann426 used trialkylphosphites, and they have been widely employed since that time, both with and without solvents.80,85,93,95,97,352 The simple dialkyl- and diarylfuroxans usually require more vigorous conditions (e.g., refluxing triethyl phosphite) than do strained derivatives or the benzofuroxans.85,97... [Pg.316]

Tris(trimethylsilyl)phosphites, analogous to trialkylphosphites, undergo Perkow reaction with a-halo carbonyl compounds to give vinyl phosphates.223 Reaction of a-chloroketone 19 with trimethylphosphite produces dimethyl enol phosphate 20, which is further converted to b is [trimethyls ilyl] esters 21 using MeaSiBr. 21 is also produced directly from a-chloroketone 19 on reacting with P(SiMe3)3. [Pg.372]

The second step, involving the reaction of the cyclic thiocarbonate intermediate formed above with trialkylphosphite, is of great interest. The phosphite P attacks the S of the thio-carbonyl group, generating a cyclic dialkoxycarbene, as shown below ... [Pg.185]

In hydrolysis with trialkylphosphites, a first order in phosphite and a second order in water were determined [138]. These observations provide evidence that the reaction proceeds via a concerted mechanism with the participation of two water molecules. In Scheme 2.107, two alternative routes for hydrolysis of trimethylphosphite are illustrated. [Pg.172]

The use of arenediazonium tetrafluoroborates as substrates for palladium-catalyzed cross-coupling reactions generates arylphosphonates in moderate to excellent yields (Schemes 4.238 and 4.239) [292]. While most palladium-catalyzed C—P bond-forming reactions use secondary phosphites as substrates, this approach uses trialkylphosphites. The chemistry displayed excellent functional group compatibility as arenes bearing esters. [Pg.384]

The treatment of acyl chlorides with trialkylphosphites is one of the oldest known methods for the preparation of acylphosphonates (Scheme 4.344) [503,504], The reaction was typically carried out by simply adding the phosphite to the acyl chloride with stirring. The C—P bond-forming process was exothermic, and the phosphite needed to be added slowly to maintain a low temperature. This was critical since secondary products appeared at higher reaction temperatures. One of the attractive aspects of this chemistry was that no solvents were used. The scope of the reaction chemistry was broad, and a host of acyl... [Pg.437]


See other pages where Phosphites trialkylphosphites is mentioned: [Pg.504]    [Pg.299]    [Pg.409]    [Pg.243]    [Pg.244]    [Pg.244]    [Pg.280]    [Pg.281]    [Pg.282]    [Pg.207]    [Pg.504]    [Pg.117]    [Pg.103]    [Pg.143]    [Pg.144]    [Pg.144]    [Pg.375]    [Pg.324]    [Pg.163]   
See also in sourсe #XX -- [ Pg.287 , Pg.291 , Pg.295 , Pg.300 , Pg.304 , Pg.338 , Pg.384 , Pg.437 , Pg.439 , Pg.449 , Pg.453 ]




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Trialkylphosphite

Trialkylphosphites

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