Oleg I. Kolodiazhnyi

Asymmetric synthesis of chiral N-(1-methylbenzyl)aminophosphines

The reactions of chlorophosphines 1 with (S)- or (R)-1-methylbenzylamines 2 proceed stereoselectively to give N-(1-methylbenzyl)aminophosphines 3, which were isolated as crystalline borane complexes with 100% diastereomeric purity. The absolute configuration of the new chiral compounds was established by X-ray analysis and chemical extrapolation.

C3‐symmetric trialkyl phosphites as starting compounds of asymmetric synthesis

Chiral C3-symmetric trialkyl phosphites, derivatives, of (−)-(1R,2S,5R)-menthol, and (−)-di-O-isopropylidene-1,2:5,6-α-D-glucofuranose, have been studied as starting reagents for the preparation of chiral organophosphorus compounds. The reactions involve induction at the α-carbon atom of substituted α-alkylphosphonates. The stereoselectivity of the reaction depends on the structure of the starting compounds and the reaction conditions. The configurations of the alkylphosphonates were defined by means of NMR spectroscopy and by transformation into corresponding alkylphosphonic acids.

Simple route to chiral organophosphorus compounds

Abstract Reaction of chlorides of nonsymmetrically substituted phosphinic and phosphinous acid with (−)-1,2:3,5-disubstituted-α-D-glucofuranose proceeds with very high stereoselectivity to give stereochemically pure phosphinic and phosphinous acid esters, which are starting reagents for preparation of chiral organophosphorus compounds. Stereoselectivity of the reaction depends on the nature of bases, solvent, temperature and excess of chlorophosphine.

Chiral symmetric phosphoric acid esters as sources of optically active organophosphorus compounds

Abstract Chiral symmetric di- and trialkylphosphites, derivatives of (−)-borneol, (−)-menthol and (−)-1,2:5,6-di-O-isopropylidene-α-D-glucofuranose, were studied as starting reagents for the preparation of chiral organophosphorus compounds. The reaction occurs by asymmetric induction at the α-carbon atom of substituted α-alkylphosphonates. The stereoselectivity of the reaction depends on the structure of the starting compounds and the reaction conditions. The configuration of the alkylphosphonates was established by NMR spectroscopy, by transformation into α-hydroxyalkylphosphonic acids and by X-ray crystal structure analysis.

Application of the dimenthyl chlorophosphite for the chiral analysis of amines, amino acids and peptides

Abstract The title reagent for the determination of the enantiomeric excess of chiral amino acids and peptides was prepared from (−)-(1 R ,2 S ,5 R )-menthol and PCl 3 . Its use as a chiral derivatizing agent for the determination of the enantiomeric content of amino acids and peptides by 31 P NMR is described.

Stereoselective oxidation of N-phosphor (III) substituted amino acids

Abstract Stereoselective synthesis of the N-phosphor (V) substituted amino acids 2 via the oxidation of N-phosphor (III) derivatives of amino acids 1 with CXCl 3 ROH are described. The mechanism and stereochemistry of the reaction are studied. by means of NMR spectroscopy. It is shown that the reaction proceeds via the formation of halogenophosphorane intermediates 4.

STEREOSELECTIVE REACTIONS OF CHIRAL AMINES WITH RACEMIC CHLOROPHOSPHINES

Racemic chlorophosphines react stereoselectively with chiral l-phenylethylamines or amino acid esters to give diastereomerically enriched aminophosphines 3, which were isolated as diastereomerically pure crystalline borane complexes. Oxidation, thionation, the reaction with methyl iodide provide optically active derivatives of aminophosphines. (R,S)- and (S,S)-stereomers of phosphinic acid amides were separated by crystallization and a flash-chromatography. The stereochemical properties of phosphorus acid amides were investigated. The mechanism of asymmetric induction at the trivalent phosphorus atom was rationalized.

ASYMMETRIC INDUCTION IN THE REACTION OF NONSYMMETRICAL PHOSPHINIC AND PHOSPHINOUS ACID CLORIDES WITH DERIVATIVES OF D-GLUCOFURANOSE

Abstract Reaction of nonsymmetrically substituted chlorophosphines (1–3) with (−)-1,2:3,5-di-O-isopropylidene-α-D-glucofuranose (1) or (−)-1,2:5,6-di-O-cyclohexylidene-α-D-glucofuranose (5) proceeds with high stereoselectivity to give stereochemically pure phosphinic acid esters (6–8), which are starting compounds for the preparation of chiral organophosphorus compounds. Reaction of benzyl-phenylphosphinous acid chloride with (1) leads to optically pure phosphinous acid ester (9). The stereochemistry of the reaction is studied in dependence on the nature of the base, solvent, temperature and excess of chlorophosphine.

Alkylamides of trivalent phosphorus-acids: phosphorus–nitrogen diad tautomerism

Abstract Alkylamides of trivalent phosphorus acids 1 exist in prototropic equilibrium with PH–iminophosphoranes 2 . Phosphorus–nitrogen diad tautomeric equilibrium 1 ⇌ 2 depends on the nature of solvents and the substituents at the phosphorus and nitrogen atoms shifting towards the tautomeric form possessing the least mobile proton.

Synthesis of Phosphonic Acids Possessing Isoindolin-1-one Moiety: Unexpected Acid-Catalyzed C-P-Bond Cleavage

Phosphonic acids bearing isoindolin-1-one moiety were synthesized by dehydrative aromatization of the corresponding epoxyisoindolyl phosphonates. A mechanism for the unexpected acid catalyzed dephosphorylation was proposed.