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A new diastereoselective synthesis of α-aminophosphonates has been developed, based on the reaction of trialkyl phosphites with a chiral imines, derived from (R)- or (S)-1-(α-aminobenzyl)-2-naphthol, in the presence of trifluoroacetic acid. The major diastereomer of obtained aminophosphonates can be separated by crystallization from an appropriate solvent. The desired α-aminophosphonic acids can be obtained in enantiopure form by treating the corresponding diastereomers with HCl.

In this report, we present the application of Pudovik reaction in the synthesis of chiral organophosphorus compounds and shown this reaction to be a promising way to enantiopure aminophosphonic acid derivatives. Cyclization reactions are a new, most efficient strategy for stereoselective synthesis of α-aminophosphonates, namely an intramolecular type of interaction of the P(III) atom and an imino group.

The reactions of S-trimethylsilyl esters of dithiophosphoric, diamidodithiophosphoric, aryldithiophosphonic, aryltrithiophosphonic, and arylamidodithiophosphonic acids with diethyl acetal of benzaldehyde and ortho formiate and acetate were studied. On the basis of these studies, new derivatives of tetracoordinated phosphorus thioacids were obtained.

The Kabachnik-Fields reaction of citral with dialkyl phosphites in the presence alkyl amines; the imine formation reaction of E,Z-citral, R,S-citronellal, and (R)-(−)-myrtenal with primary amines; and Pudovik reactions of prenyl imines obtained with dialkyl phosphites or with O,O-dialkyl trimethylsilylphosphites were studied. On the basis of these studies, new unsaturated prenyl imines and α-aminophosphonates were prepared.

A new approach to the synthesis of polycyclic hexacoordinated phosphorus derivatives was developed. It is based on the reaction of alkylene chlorophosphites with salicylaldehyde diimines without a base catalyst.

The reactions of O,O-dialkyl dithiophosphoric acids with triisobutyl borate, ammonium O,O-diisobutyl dithiophosphate with fluorodiisobutyl borate, and tetraphosphorus decasulfide with triisobutyl borate were studied. On the basis of these studies, new boron derivatives of dithiophosphoric acids were obtained. Low frequency ultrasonic irradiation (22 kHz, power 130 W) leads to reduction in reaction temperature and time in the reactions studied.

We developed a new approach to the synthesis of saturated and unsaturated phosphoruselementocontaining heterocycles was developed; we based it on the addition reactions of various proton nucleophil...

Here we report on a new type of chiral molecular propellers - trianhydrides of trithiophosphorous acid and organic thioacids.

Glycidol (1) reacts with PCl3 at low temperature in the absence of base forming (E)-2-chloro-4-chloromethyl-1,3,2-dioxaphospholane ((E)-2) in a highly diastereoselective manner. At room temperature (slow) or during the distillation (fast) (E)-2 turns into an equilibrium mixture of isomeric (E)- and (Z)-2. The original configuration on the phosphorus centre may be conserved by low temperature oxidation of (E)-2 to (E)-2-oxo-2-chloro-4-chloromethyl-1,3,2-dioxaphospholane ((E)-3). The phosphorylation of 1 proceeds through the formation of P-H spiro-phosphorane (5). A new, simple and efficient method of the generation of stable hydrophosphoranes is proposed.

New convenient methods of synthesizing useful mixed organic derivatives of B, Si, Ge, Sn, Pb, As and phosphorus (IV) thioacids with a P(S)S-E fragment were developed. Their spectral, structural and chemical properties were studied.

The reactions of tetraphosphorus decasulfide and 2,4-bis(4-alkylthio)-2,4-dithioxo-1,3,2λ5, 4λ5-dithiadiphosphetanes with disulfides and thioacetals were studied. The reactions were found to give some novel organothiophosphorus compounds.

S-Trimethylsilyl esters of dithio-and tetrathiophosphoric acids were obtained in the reaction of tetraphosphorus decasulfide with alkoxy-and alkylthiotrimethylsilanes, trimethylsilyl enol ethers and bis(trimethylsiloxy)alkylenes and phenylene.

Lawesson's reagent reacts with dialkyl disulfides to form S,S-alkyl-S'-alkyl (4-methoxyphenyl) phos phonotrithiolothionoates with P-S-S-Alk bonds. The reactions of 2,4-bis(4-alkoxyphenyl)-2,4-dithioxo-1,3,2λ5,4λ5-dithiadiphosphetanes with thioacetals and acetals were reinvestigated and were shown to give trithio- and dithiophosphonates including an aldehyde fragment in their composition.

The reactions of tetraphosphorus trisulfide with thioacetals, aminals, sulfenamides and disulfides were studied. The reactions were found to give organothiophosphorus compounds and to be facilitated by organic amines and benzoyl peroxide.

The substitution and addition reactions have been studied in the series of thioloderivatives of P(III) acids. The reactions have been shown to proceed with the rupture of the P-S bond, the phosphorus coordination being preserved.

A new and efficient route for the synthesis of cyclic aminophosphonic acids by the reaction of dialkylchlorophosphites with β-aldiminoalcohols has been described.

The possibility of using of easily available 1-(α-aminobenzyl)-2-naphthols as chiral auxiliaries in the synthesis of non-racemic α-aminophosphonates has been shown.

The problems of synthesis and transformations of new organoelement reagents containing sulfur, silicon and phosphorus (S-P-O-Si, P(S)-S-Si) are discussed.

The kinetics of the basic hydrolysis of O-alkyl-O-p-nitrophenyl-chloromethylphosphonate in aqueous micellar solutions of cetylpyridinium bromide (CPB) and the aminolysis of these substrates by n-hexylamine in the reverse micelles of polyethylene glycole-600-monolaurate (PM) in toluene has been studied.

Kabachnik-Fields and Pudovik reactions were studied with the use of chiral initial reagents. In all cases the products of these reactions represent a mixture of diastereomers.

It is shown that P4S10 and (R2N)3P can be used as achiral derivatising reagents for the determination of enantiomeric excess (ee) of chiral alcohols R*OH.

The compounds exhibiting hypervalent interactions of nonbonded atoms may be used as models of prereaction and transition states of nucleophilic substitution reactions. Our studies of the molecules X(CH2)2-O-PCl2 (X ˭ H (1); SCN (2); C2H5 (3); CH3O (4); Cl (5) revealed the possibility of subtle intramolecular 1–5 attractions between the sulfur (2) [I] or the oxygen (4) or the chlorine (5) and the phosphorus atoms. The attractions influenced perceptibly only the energy of the conformers with intramolecular contacts between the heteroatoms. A substantial energetical preference of the convoluted conformers (B) in the liquid state was observed in the case of 2. 4 and 5. In contrast. the molecules 1 and 3 preferred to exist in liquid in extended conformations (A). These dramatic changes cannot be explained by steric reasons or Coulomb attractions, and thus were attributed to hypervalent attractions between the heteroatoms. The relative energies of (A) and (B) conformers were used in quantitative assess...

The use of iodine results in reactivity enhancement of phosphorus sulfides and homologues of Davy's reagent in the reactions with disulfides, aminals and thioacetals. The reactions β-diiodotetraphosphorus trisulfides with disulfides, aminals and thioacetals were studied.

The investigations of the reactions of lower phosphorus sulfides with organic substances can result in novel non-traditional methods of the synthesis of organophosphorus compounds. Tetraphosphorus trisulfide was proved to react with thioacetals, to give addition products of the a-alkyl-thioalkyl thionphosphonate structure and tetrathiophosphates.

The acetylthio- and acetimidoylthioderivatives of P(III) acids have been obtained in the reactions of thioacetamide and thioacetic acid, and tlieir derivatives with different P(II1) compounds containing groups that are easily detached. As a rule, the reactions proceed with the formation of S-phosphorylated derivatives and only very rarely can the X-phosphorylated compounds be obtained.