Ethyl phosphonates, control

Ca->,POa, inhibition/dispersion, Ca Phosphonate control, Fe stabilization MA/EA/VA Maleic anhydride/ethyl acrylate/vinyl acrylate examples Belclene 283, Polycol 90... 

Stereochemical control of a reaction can also be achieved using non-chiral catalysts, when a chiral centre already exists in the reactant, as for example in the reaction of cyano- or methoxycarbonylmethyl phosphonates with 3-hydroxy-2-(S)-alkylated products are obtained with ca. 40% de of the 2(S)-3(R)-diastereoisomers [11]. Similarly, when ethyl glycine is Ar-protected with (S)-menthone, C-alkylation under soliddiquid conditions using a non-chiral catalyst (6.4.5) provides a route to chiral a-substituted amino acids with optimum enantiomeric excesses of up to 47% [12],... 

Most of the examples in this chapter have been disubstituted alkenes, a few have been trisubstituted, but none so far has been tetrasubstituted (except cyclic alkenes) as this is the most difficult case of all. One solution49 starts with ethyl lactate 228 and uses a HWE reaction on the enantiomerically pure phosphonate 229 to make the / -enone 230 with very high selectivity. Chelation-controlled addition of a Grignard reagent gives the stereochemically pure allylic alcohol 231. Chelation control is explained in chapter 21. 

The newest active substance developed by the Rhone-Poulenc (Horriere, 1977) is ethyl hydrogen phosphonate aluminium-salt (39). Its common name is fosetyl. This fungicide is truly systemic with protectant and curative properties, primarily active against Phycomycetes fungi (Bertrand et al., 1977 Williams et al., 1977). It has been widely tested on temperate and tropical crops (Beach, 1979) and has successfully controlled many important Phytophtkora spp and downy mildew. Mixtures with... 

The synthesis of phosphonic acid derivatives by the direct oxidation of those of the corresponding phosphonous acid has been afforded very little interest (Chapter 2, Section VI.c), unlike the more controllable synthesis of derivatives of the thio- or seleno-phos-phonic acid derivatives (Chapter 5, Section II.B.4). In the present instance, the oxidation of A -protected (fmoc) (l-aminoalkyl)phosphinic esters has been carried out with NaI04 with high yields. Quantitative yields of (aminoalkyl)phosphonic acids were obtained in oxidation reactions with bromine water and with HgCl2-H20. In an alternative approach (Scheme 59), the A -protected (cbz) ethyl(l-aminoalkyl)phosphinate is initially converted into a (l-aminoalkyl)phosphonous acid diester, which is then subjected to the Atherton procedure to achieve change in valence at phosphorus. ... 

Reaction of 4-chlorophenylcarbonimidoyl dichloride with triethyl phosphite ( ). To 21 g (0.01 mole) 4-chlorophenylcarbonimidoyl dichloride 33.2 g (0.02 mole) triethyl phosphite is added dropwise and with stirring. The reaction proceeds, as indicated by the evolution of ethyl chloride, and the exothermic reaction is controlled by the rate of addition (maximum temperature approximately 40°C). Heating to 50-60 C until the generation of ethyl chloride ceases, and rectification under vacuum, yields 33.6 g (82 %) of the corresponding bis-phosphonate, b.p. 190-195° C/0.05 mm. 

Styrene monomers with phosphonic acid placed on side chains with different spacer length have been polymerized by a radical mechanism to obtain membranes with controlled water uptake at high ion exchange capacity (lEC) values. The proton conductivity of polymers containing ethyl and hc grl spacers between the polystyrene (PS) main chain and the phosphonic acid reached similar conductivity between 10 and 140 Although... 

Synonyms Ammoninm salt, ammoninm ethyl(aminocarbonyl)phosphonate Ammonium ethyl carbamoylphosphonate solution DPX 1108 Krenite Krenite brush control agent. 

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