Phosphonic diamides

Acryhc esters dimerize to give the 2-methylene glutaric acid esters catalyzed by tertiary organic phosphines (37) or organic phosphorous triamides, phosphonous diamides, or phosphinous amides (38). Yields of 75—80% dimer, together with 15—20% trimer, are obtained. Reaction conditions can be varied to obtain high yields of trimer, tetramer, and other polymers. 

Attempts to initiate formation of a nitrene, and its rearrangement to the iminooxo-phosphorane 80, by subjecting l-chloroamino-2,2,3,4,4-pentamethylphosphetane 1-oxide to a-elimination with sodium methoxide proved unsuccessful48). In contrast, however, the phosphorylhydroxylamides 88 rearrange in the presence of tert-butyl-amine to the heterocumulene 89 and then add base to give the phosphonic diamides 90 (>90%)49). The reaction is reminiscent of the well-known Lossen degradation. 

Diethyl dl-1 -aminobenzylphosphonate has been prepared by a Mannich reaction of diethyl phosphite, benzaldehyde, and ammonia, resolved as its D-mandelate salt, and hydrolysed to give (+)-l-aminobenzylphosphonic acid.27 While the tetraethyl-diamide (33) reacts with benzaldehyde to give the expected phosphonic diamide (34), the corresponding tetramethyl-diamide reacts, with migration of the dimethyl-amino-group, to give (35).28... 

An example of the diazaphosphoridine ring system has been reported.67 The NN -di-t-butyl phosphonic diamide (65), prepared conventionally, is treated with t-butyl hypochlorite to give the mono - iV-chl or o-der ivative (66), which readily loses HC1 to give 1,3,2-tri-t-butyl diazaphosphoridine 3-oxide (67), which can be isolated by sublimation. Methanolysis of (66) at 100 °C yields the phosphonic hydrazide (68). 

A new class of sulfurated heterocycles - dithiadiazaphospholidine S-oxides 170 - was obtained by treatment of phosphonic diamide 168 with sulfur monochloride its precursor heterocycle 169 was detected in the mixture. However, it was found to be susceptible to oxidation and only S-oxide 170 was isolated (1995CC1449 Scheme 88). 

The intermediacy of phosphonoamidic-sulfonic anhydride (476) in the rearrangement of O-sulfonyl-N-phosphinoylhydroxylamine (477) with tert-butyla-mine was confirmed. The observed products, phosphonoamidate anion (478) and phosphonic diamide (479) correspond to attack of tert-butylamine at sulphur and phosphorus atoms of the anhydride (Scheme 110). ... 

Extraction processes (TRUEX, PUREX, Talspeak, DIAMEX, PARC, etc.) generally involve complexation of transplutonium elements by alkyl phosphines, phosphine oxides, phosphoric acids, carbamoyl phosphonates, diamides, and thiophosphinates in aqueous/organic extractions, within derivatized solid supports, or on coated particles. There are excellent reviews of the processes and significant complexes by Mathur et al. and selected chapters in The Chemistry of the Actinide and Transactinide Elements to be published in 2003. " Work on the separation for nuclear waste management in the United States, France, and Russia have been reviewed. " ... 

N2PSiCi4H27, Phosphonous diamide, N,N,N, N -tetramethyl-p-[phenyl(trimethylsilyl)methyl-] 24 110 N2P2S3C36H30, Phosphorus(l+), x-nitrido-bis(triphenyl-... 

PNSi2CgH24, Phosphinous amide, P,P-di-methyl-Af, Af-bis(trimethylsilyl)-, 25 69 PN2SiCuH27, Phosphonous diamide,... 

Waschbusch, R., Carran, J., Marinetti, A., and Savignac. P, Synthetic apphcations of dialkyl (chlo-romethyl)phosphonates and V,V,V, V -tetraalkyl(chloromethyl)phosphonic diamides. Chem. Rev., 91, 3401, 1997. 

New information on the three-membered phosphorus(v) heterocycles which are often postulated as reactive intermediates comes from a study of the reactions of phosphonic diamides R P(0)(NHR )2. On treatment with t-butyl hypochlorite these are converted into the mono-N-chloro-amides, which with base lose hydrogen chloride, forming the diazaphosphoridine oxide (53). The structure is supported by spectroscopic data and by the quantitative formation of the hydra-zide (54) on reaction with methanol. New phosphorus(v)-nitrogen-phosphorus(in) systems (55) have been synthesized by transamination reactions between... 

T riamiphos, 5-amino-3-phenyl-1H-1,2,4-triazol-l -yl-N,N,N, N -tetramethyl-phosphonic diamide, marketed as Wepsyn", has been used primarily in floriculture (roses) and apple orchards for the control of powdery mildew (Koopmans, 1960). In addition to its prophylactic use, it is absorbed by the plants and has a curative effect. According to Magendans and Dekker (1966), triamiphos primarily inhibits the formation of haustoria, but it also reduces spore formation. It also has insecticidal properties, mainly against aphids. Today, triamiphos has been replaced by other pesticides because it is expensive to produce and is very toxic to warmblooded organisms, its acute oral lDjo being 20 mg/kg for rats. 

Also in this group 0-(2-nitro-3,4,6-trichlorophenyl)-N,N,N, N -tetramethyl-phosphonic diamid (37) developed by E>emecko and Konecny (1970), is very effective against powdery mildew of cucumber and barley. It also has an acaricidal effect. 

Aromatic isocyanates, particularly those containing electron-attracting substituents, react noticeably more easily than aliphatic isocyanates. In the former case it often suffices to leave the components for some hours at room temperature in a water-pump vacuum, whereas for aliphatic compounds boiling under reflux is usually necessary and sometimes use of a higher-boiling solvent such as decalin. The best catalysts are cyclic phosphine oxides of type (1) (phospholene oxides)862 and cyclic phosphonic diamides of type (2) (1,3,2-diazaphospholidine oxides).863 The best results were obtained with compound (1, R = C2H5) (for its preparation see Campbell et a/.862) the phenyl compound, although more readily prepared,864 is somewhat less reactive. The amounts of catalyst needed are 0.1% for (1) or 0.5% for (2). 

The addition of acyl hydrazides to (l,2-alkadiene)phosphonic diamides (325) yields the 1,2,3-diazaphospholidine 3-oxides (326). Interaction of the phospho-nite esters (327) (X = Cl or Br) with a,P-unsaturated carboxylic esters, nitriles, ketones, or related compounds, gives quaternary products which decompose in boiling benzene to produce the dihydrophospholes (328). ... 

A similar cheletropic condensation occurs between a phosphenium cation and a hydra-zone from crotonaldehyde (equation 27) to give a cyclic phosphonic diamide derivative. ... 

Given a sufficiently strong base, the activation produced by the phosphoryl group next to an adjacent C—H bond will allow deprotonation and the generation of a highly reactive carbanion. Butyllithium has been commonly used for this purpose, but a preference has been shown in recent work for Ida. Treatment of the anion from methyl methyl(4-morpholinyl)phosphinate (284) with farnesyl chloride yields 285, which, on acidolysis, affords the phosphonic acid 286, employed in the synthesis of a pyrophosphonate analogue of farnesyl pyrophosphate ". Alkylation of the carbanion from the chiral phosphonic diamide 287 (X = Me or higher alkyl) leads to the diastereoisomeric phosphonic... 

Much attention has been devoted to the conversion of aldehydes into the trimethylsilyl ethers of (a-hydroxyalkyl)-phosphonic acids 210 or analogous -phosphinic acids, or of the corresponding (a-hydroxyalkyl)phosphonic diamides 211 by the use of dialkyl trimethylsilyl phosphite or Me3SiOP(NEt2)2 (or other phosphorodiamidite) It is a reaction which occurs very readily, even at room temperature, and the ready methanolytic or hydrolytic removal of the silyl protecting group makes the procedure an attractive alternative to the direct synthesis of the (a-hydroxyalkyl)phosphonic acids from dialkyl hydrogenphosphonates and carbonyl compounds. Silyl-protected hydroxy-phosphonic and -phosphinic acid derivatives are useful for further synthetic development. ... 

New developments in the synthesis of a-hydroxy phosphonic acids and their derivatives have concentrated on their asymmetric formation. The chiral phosphonic diamides (629) (in which R = isopropyl, 2,2-dimethylpropyl, or benzyl or a derivative thereof) in either racemic or optically active forms were converted into their anions and allowed to react with aldehydes to give the products (630) the diastereoisomeric composition of the latter could be ascertained by the use of P NMR spectroscopy, and after acidic hydrolysis and subsequent methylation (diazomethane) it was possible to isolate optically active forms of the dimethyl esters of (l-hydroxyalkyl)phos-phonic acids, the (/ ,R)-diamide giving rise to the (5)-acids as their esters. The best results were achieved when R = Bu CFl2, and enantiomeric excesses were generally above 85% . 

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