Aminophosphonic acid

Dime thy1(2-pho sphoe thy1)-(N-methyl-N-phosphoethyl)-2-aminoethylammonium (iodide) (CgH250 N2P2 ), H2L/HL.H 6.46 h l/H L.H 5.45 H I./HjL.H 1.5 76MD 

72AU Other reference 67MR 

Ethylenebis[imino(dimethy1)methylenephosphonic acid] (continued) 

Estimated value calculated from values at 3.0 ionic strength. 

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MIXED-LIGAND COMPLEXES (MLC) OF La WITH AMINOPHOSPHONIC ACID GRAFTED ON SILICA AND ARSENAZO I, III AND XYLENOLE ORANGE... 

OLEKSYSZYN Aminophosphonic acid synthesis Synthesis ol 1-aminoalkanephosphonic and 1-aminoa([Pg.278]

This group was used as a protective group and chiral directing group for the asymmetric synthesis of o -aminophosphonic acids. It is cleaved by acid hydrol-... 

Racemic and optically active a-aminophosphonic acids, derivatives of various heterocycles 97ZOR1605. 

Interesting developments in simple azetidine chemistry continue to be reported. The apparently general acetylative dealkylation of Af-tert-butyl-3-substituted azetidines 6 (R = Bu ) in the presence of boron trifluoride provides a two-step route to azabicyclobutane 7 from 6 (R = Bu, R = Cl). An aqueous solution of 7 reacts with ethyl chloroformate to give 8. Relatively unexplored 3-azetidinones 9 (R = Ac or NO2) are available from 3-acetoxya2Ktidine 6 (R = Ac, R = OAc) which is obtained by acetylative dealkyation of 6 (R = Bu , R = OAc) <96JOC5453>. 3-Substituted azetidines can be utilized in the synthesis of polyfunctional y- and S-aminophosphonic acid derivatives <95TL9201>. 

A. Aminophosphonic Acids.— The Michael addition of a dialkyl phosphite to acrylonitrile leads to C—P bond formation and the production in high yield of derivatives of 2-aminoethylphosphonic acid (45). This synthetic method appears to be preferable to those already described. ... 

Stereoselective hydrolysis of racemic l-(//-phenylacetylamino) alkanephos-phonic acids performed in the presence of penicillin acylase under the kinetic resolution conditions gave both the unreacted substrates and the products - the corresponding 1-aminophosphonic acids in high yields and with full enantioselec-tivity. The unreacted A -acyl derivatives were hydrolysed chemically and in this way each enantiomer of the free acid was obtained (Scheme 5). ... 

Biological Activity of Aminophosphonic Acids and Their Short Peptides... 

Flynn, G.A., Beight, D.W., Bohme, E.H.W., and Metcalf, B.W., The synthesis of fluorinated aminophosphonic acid inhibitors of alanine racemase, Tetrahedron Lett., 285, 1985. 

Tyka, R. and Oleksyszyn, J., a-Aminophosphonic Acids, Polish Patent 105,825, 1980. 

Glowiak, T. and Sawka-Dobrowolska, W., Absolute configuration of optically active aminophosphonic acids, Tetrahedron Lett., 3965, 1977. 

Wieczorek, J.S. and Gancarz, R., Aminophosphonic acid derivatives of fluroene, Rocz. Chem., 50, 2171, 1976. 

Hamilton, R., Walker, B., and Walker, B.J., A highly convenient route to optically pure a-aminophosphonic acids, Tetrahedron Lett., 36, 4451, 1995. 

Chloromethylphosphonamide 104 has been alkylated with diastereoselectivities up to >95%. The corresponding azido compounds 106 were obtained by nucleophilic displacement, with partial to full stereospecificity <2000HA528>. This two-step process can lead to aminophosphonic acids after reduction of the azido group and hydrolysis of the chiral appendage (Scheme 7). 

A useful review of the chemistry of a-aminophosphonic acids has been published.47 Treatment of a-aminomethylphosphonic mono-esters with bromoacetyl halides... 

The beneficial effect of surfactants on enantioselective hydrogenations in water was exploited in the synthesis of a-aminophosphinic and a-aminophosphonic acids. These compounds are stmctural analogues of a-aminocarboxylic acids and their peptides find use as herbicides, bactericides and antibiotics [150,151]. With [Rh(BPPM)(COD)]Bp4 and similar catalysts fast ractions and e.e.-s up to 98% could be obtained in water in the presence of SDS (Scheme 3.12). 

Kabachnik MI, Medved TY (1952) New synthesis of aminophosphonic acids. Dokl Akad Nauk SSSR 83 689-692... 

Novel syntheses of a-aminophosphonic acid derivatives (453 and 454) were disclosed, using the Beckmann rearrangement as a key synthetic step. The ring size was crucial and only seven-membered cycles could be formed in fair yield (51-62%) (equations 193 and 194). 

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