R. A. Cherkasov

INTERACTION OF SULFENYL CHLORIDES WITH UNSATURATED ORGANOPHOSPHORUS COMPOUNDS: AdE3 REACTION MECHANISM AND REGIOCHEMISTRY OF ADDITION

Abstract As evidenced by 1H, 31P, and 13C NMR spectroscopy, phenylsulfenyl chloride, like phosphonosulfenyl chloride,1 adds to vinylphosphonates to produce a mixture of two regioisomers. Thermodynamic stability of β-chloroadducts is greater than that of α-chloroisomers. The 1,2-addition of C6H5SCl to isopropenyl-and styrylphosphonates and unsaturated thionophosphoryl compounds is regiospecific. Kinetic studies have established that the reactions might proceed by the AdE3-mechanism involving two molecules of an unsaturated reagent. The substituents at phosphorus and the carbon-carbon double bond in phosphonates affect the structure of the transition state in the limiting stage of the reaction, as does the medium. The effect of the organophosphorus group in the unsaturated reagent and sulfenyl chloride on the mechanism of the AdE-process has been analyzed.

Enthalpies of specific interaction of heteroatom derivatives of three-coordinate phosphorus with chloroform

The nature of hydrogen bonds formed by chloroform with three-coordinate phosphorus derivatives containing sulfur, silicon, and chlorine atoms and their carbon analogs was revealed by analysis of the experimental enthalpies of specific interactions. The main donor centers in the examined compounds were found to be oxygen atoms and π-electron systems of aromatic rings. Sulfur atoms give rise to weaker complexes as compared to oxygen. Phosphorus, chlorine, and silicon atoms are not involved directly in specific interactions with the solvent.

Electronic effects on the enthalpy of specific interaction of three-coordinate phosphorus compounds and acetals with chloroform

The effect of electronic factors in five- and six-membered cyclic three-coordinate phosphorus compounds and acetals on the enthalpy of their specific interaction with chloroform was estimated.

Applicability Limits of Calculation Methods for Estimating the Enthalpy of Vaporization of Organophosphorus Compounds

Quantitative relationships used today for calculating the enthalpies of vaporization of organophosphorus compounds are analyzed. The parameters of equations used in these calculations largely depend on specific structural features and are common for closely related compounds only. With various P(III) derivatives as examples, narrow ranges are distinguished in which the enthalpies of vaporization can be estimated from the boiling points using common relationships. The group contributions of phosphorus-containing fragments for calculations by the additive scheme are determined.

Structure and Molecular Lability of N-(Thio)phosphoryl(thio)amides: XL. Interpretation of the N-Benzoyl(acetyl)amidothiophosphate → N-Thiobenzoyl(acetyl)amidophosphate Rearrangement by means of 1H, 13C, and 31P NMR Spectroscopy

The N-benzoyl(acetyl)amidothiophosphate→N-thiobenzoyl(acetyl)amidophosphate in CCl4 and toluene-d8 solutions was studied by means of 1H, 13C, and 31P NMR spectroscopy. The transformation of one amide form to the other is accompanied by intramolecular migrations of the amide proton and (thio)phosphoryl group and is a complex equilibrium of two dynamic systems.