Edward E. Nifantyev

Nature of acid-catalyzed alcoholysis of amides of trivalent-phosphorus acids

Abstract To study the chemical nature of the acid catalysis of amides oftrivalent-phosphorus acids (ATPA) alcoholysis the most important procedural problems have been solved. Simple and efficacious techniques for the purification of original ATPA from amine hydrohalides have been worked out. A precise and reliable way has been chosen to control the residual amount of amine hydrohalides in ATPA having been subjected to the various purification procedures. The nature of the dependence of alcoholysis rate constants for ATPA of different structures on the aminehydrohalide concentration has been established. The general acid catalysis was established using the Bronsted equation, so that the process includes the formation of a catalytic H-complex incorporating substrate and catalyst on the whole. Amides P(III) of different types treated with anhydrous hydroborofluoric acid readily form the corresponding P-protonated salts. The conversions of corresponding products of complete protonation have been investigated. The structure of P-protonated salt 23 has been studied by means of X-ray analysis.

SYNTHESIS OF 1,2-O-ISOPROPYLIDENE GLYCERO-THIOLO-(DITHIOLO)-PHOSPHOHOMOCHOLINES. A NEW THION-THIOL ISOMERIZATION OF ALKYLENE PHOSPHOROTHIOATES

Abstract A convenient method for thion-thiol isomerization of 1,3-alkylen-phosphorothioates under the action of phosphonium bromides is offered. The possibility of exo-and endo-cyclic isomerisation at the expense of a change of substituents on phosphorus atom is considered. Cyclic 1,2-O-isopropylideneglycerothiolo-and dithiolophosphates have been reacted with trimethylamine to yield in such a way 1,2-O-isopropylideneglycero-thiolo-(dithiolo)phosphohomocholines which are of interest for the synthesis of phospholipids.

Anthracene Diols in the Synthesis of Phosphacyclophanes

The first phosphacyclophanes have been synthesized from anthracene derivatives. For this purpose, the reactions of 2,6-anthracene diol and 9,10-diacetoxy anthracene with phosphorous acid triamides have been studied. Some chemical properties of the obtained compounds have been investigated.

Dismutation of diamidoarylphosphites

Some examples of spontaneous dismutation of diamidoarylphosphites in different solvents were studied, and features of the process were revealed.

Sterically controlled cyclization of 3′,4′,5,7-tetramethyldihydroquercetin amidophosphites. New synthesis of phostones

A new sterically controlled reaction of α-hydroxyketones with phosphorus acid triamides resulting in new four-membered phostones is reported.

THE SYNTHESIS AND STRUCTURE OF P(III)-PHOSPHORYLATED 2-AMINOPYRIDINES AND THEIR DERIVATIVES

Abstract A number of the derivatives of 2-aminopyridine and diisopropyl-phosphinous, neopentylene- and pyr-ocatecholphosphorus acids 1−3 and also the diphosphorylated derivative 4 have been obtained. Phosphinite 1 was alkylated by triethyloxoniumtetrafluoroborate with the formation of quasi-phosphonium salt 5 and was protonated by hydrogen chloride at the endocyclic nitrogen atom to form pyridinium salt 6. The structure of all obtained compounds was studied by 1H, 13C, 15N and 31P NMR spectroscopy and it was shown that they exist predominantly in the phosphoaminopyridine form A.

Dismutation of Bisphosphorylated Aromatic Diols

Abstract The first study of the dismutation of aromatic diol bisdiamidophosphites has been performed. Derivatives of condensed aromatic systems dismutate more rapidly than their mononuclear analogues. Amide derivatives with aliphatic substituents at the nitrogen atom undergo dismutation more readily than their heterocyclic analogues. In methylene chloride, the process proceeded most rapidly regardless of the aromatic component and the substituent at the phosphorus atom. Apolar solvents (benzene and diethyl ether) did not favor the dismutation. Temperature had no effect on the time of dismutation, and a catalyst decreased it by a factor of 1.5–2.

1,3,2-Oxazaphosphorinanes in rhodium(I) complexes

Abstract Acetylacetonate complexes of rhodium(I) with 1,3,2-oxazaphosphorinanes were obtained. The structure and features of the stereochemistry of these compounds were studied by X-ray crystallography, and 1H and 31P NMR spectroscopy. The places 1,3,2-oxazaphosphorinanes take in the spectrochemical series of organophosphorus ligands is discussed.

UNUSUAL SYNTHESIS OF BICYCLO-[3,2,1]-2,7,8-TRIOXA-1-PHOSPHAOCTANE SYSTEM

Abstract An unusual reaction leading to formation of bicyclo-[3,2,1]-2,7,8-trioxa-1-phosphaoctane framework by acylation of 2-thio(seleno)-2-dimethylamino-5,6-isopropylidene-1,3,2-dioxaphosphepanes was revealed.

THIONOPHOSPHATES OF CYCLODEXTRINS

Abstract The preparation of thionophosphates of cyclodextrins by using P(III)-reagents has been investigated.