Cyclic phosphonic acid

The hydrolyzed products from the reaction of long chain olefins having even carbon numbers (Cs-Cj 4) with oxygen and phosphorus were said to have excellent surface active properties In contrast to Willstatter and Sonnenfeld 3) who reported that olefins used in excess of that required by the composition olefin P2O4 were not consumed, Cummins found recently that excess olefin gives in addition to the phosphorate six- and eight-membered cyclic phosphonic acid esters, e.g. 38 and 39 when styrene is used. Unlike the phosphorates ... 

S)-(3-Hydroxy-2-phosphonomethoxypropyl)adenine (140) is a useful intermediate its reaction with DCC yields the cyclic phosphonic acid (141) from which the ester (142) can be obtained by treatment with methoxide. With DCC and morpholine,... 

Chiral cyclic esters of phosphonic acid in the synthesis of coordination compounds and homogeneous asymmetric catalysis 99KK83. 

Various cyclic phosphonate esters 36 and 37 have been described previously as products from the HHT reaction of 25 with the appropriate cyclic phosphite. A complementary method has also been developed from the V-protected phosphonyl chloride 84, which was readily prepared from the corresponding phosphonic acid 83. Subsequent reaction of 84 with the appropriate diol produced the cyclic phosphonate esters 85 (63). Higher homologs of 85 have also been prepared from the analogous propane or butane diols. 

The cyclic phosphonate (115) is hydrolysed in acid with loss of MeOH whereas in basic solutions ring-opening occurs almost exclusively - a result in accord with the greater restriction on pseudorotation in a penta-covalent intermediate under basic conditions. 

A successful synthesis (Scheme 19) of the phosphonic acid analogues of D-and L-penicillamine commences with the cyclic phosphorochloridite (132). Other attempts using (132 ... 

Standard cyclisation methodology was used to access the cyclic monophosphinic acid derivative 78 by reaction of ammonium phosphonate and ethyldiisopropylamine, followed by the addition of chlorotrimethylsilane, with 2,2 -bis (bromomethyl)-l,l -biphenyl. Silane reduction of 78 gave the secondary phosphine. The secondary phosphine borane complex 79 could be used in alkylation or Michael addition reactions. For example the Michael adduct 80 was produced in high yield by treatment of 78 with a NaH suspension in THF followed by the addition of diethylvinylphosphonate . 

Hoppe, I., Schollkopf, U., Nieger, M., and Egert, E., Asymmetric addition of a chiral cyclic phosphite to a cyclic imine — synthesis of phosphonic acid analogues of d- and L-penicillamine, Angew. Chem., Int. Ed. Engl., 24, 1067, 1985. 

AUenic phosphonic acids undergo cyclization reactions in the presence of electrophilic reagents, i.e. proton, bromine (in CHC13) and Hg(OAc)2 (in HOAc), to afford five-membered cyclic compounds [71]. The reaction rate depends greatly on the struc-... 

Despite continnons progress in amide bond formation, the acylation of hydroxylamine nnder carbodiimide promotion is often contaminated by Af,0-diacylation even with sub-stoichiometric amounts of acids. Appendino and colleagues have developed a practical solution to the problem by combining the in situ activation of carboxylic acids 102 with the cyclic phosphonic anhydride PPAA (103), and the generation of hydroxylamine from its corresponding hydrochloride to form 104 (Scheme 54). 

Cyclic Acetals of Formyl Phosphonic Acid Esters... 

Polyester One of the most successful commercially available FR polyester fiber is Trevira CS, which is produced by incorporating a comonomeric phosphinic acid unit into the PET polymeric chain. Examples of FR additives used in polyester are bisphenol-S-oligomer derivatives (Toyobo GH), cyclic phosphonates (Antiblaze CU and 1010, Rhodia), and phosphinate salts (Clariant). All these FRs do not promote char formation.3... 

Derivatives of phosphonic acids, RP==O(0H)2, can be prepared by several different oxidative methods. Primary phosphines RPH2 are oxidized to phosphonic acids by hydrogen peroxide or by sulfur dioxide thus, phenylphosphine gave benzenephosphonic acid (96%) on reaction with sulfur dioxide at room temperature in a sealed tube. Phosphinic acids, RI sO(OH)H, can also be oxidized to the corresponding phosphonic acids with hydrogen peroxide. Ozone oxidized the dioxaphosphorane (54) to the phosphonic ester in 73% yield. Ozone is also capable of stereospecific oxidation of phosphite esters to phosphates. For example, the cyclic phosphite (SS) was oxidized to the phosphate (56) with retention of configuration. Peroxy acids and selenium dioxide are other common oxidants for phosphite esters. 

Tetramethyl-3-thiazoline was used as a model compound to study the hydrophosphonylation of cyclic imines for the production of pharmaceutically interesting a-amino phosphonates (eq. (19)) [172]. The resulting thiazolidinyl-phosphonate can be regarded as an lV,S-protected phosphonic acid analogue of the a-amino acid D-penicillamine which functions, e. g., as an HIV-protease inhibitor. 

Several addition reactions to C=N groups have been developed in recent years with a high synthetic potential but with no commercial use so far [12 zb]. The addition reaction of (MeO)2PHO to cyclic imines (58-60), an interesting method for the preparation of a-amino phosphonic acids, seems to be an exception [46]. While ee values of the heterobimetallic catalyst (cf. Section 3.1.5) are very high, TON and TOP values are relatively low. 

Osipov, S. N., Artyushin, O. I., Kolomiets, A. F., et al. (2001) Synthesis of racemic cyclic amino acids Synthesis of fluorine-containing cyclic a-amino acid and a-amino phosphonate derivatives by alkene metathesis. Fur. J. Org. Chem., 3891-3897. 

Cyclic trimetaphosphonic acids have been obtained as the products from the hydrolysis of phosphonic dichlorides, - but a further report indicates an unusual reaction course during the hydrolysis of the 2-chloroalkylphosphonothioic dichlorides (87) with 6M-HC1, to give (88) and (89) in the approximate proportions 2 1. ... 

The first nomnicrobial asymmetric synthesis of fosfomycin was based on the use of tartaric acid as chiral auxiliary to induce the appropriate bifunctionalization of prochiral (Z)-l-prope-nylphosphonic acid (Scheme 4.27). Thus, the reaction of (2S,35)-tartaric acid derivatives with (Z)-l -propenylphosphonic dichloride in CH2CI2 at -10°C gives cyclic phosphonates that undergo... 

Pudovik, A.N., and Krupnov, G.P., New method of synthesis of esters of phosphonic and thiophosphonic acids. Part 36. Synthesis of derivatives of phosphonic acids with cyclic radicals in the ester groups, Zh. Obshch. Khim., 31, 4053, 1961 J. Gen. Chem. USSR (Engl. Transl), 31. 3782, 1961. 

In the route to amino phosphonic acids, dialkyl l-(alkoxycarbonyl)methylphosphonates, in the presence of NaH in THF or DME, are alkylated with activated aziridines, 3-aIkoxyazetidinium salts, ° ° and cyclic sulfate derived from (5)-l,2-propanediol ° ... 

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