An overview about the activation of white phosphorus, P4 with main group elements and compounds is given.

P4 Activation by Main Group Elements and Compounds

On the Basicity of Organic Bases in Different Media

o-Quinone methide (1) has been produced in water both thermally and photochemically from (2-hydroxybenzyl)trimethylammonium iodide (2). Michael addition reactions of 1 to various amines, and sulfides, including amino acids and glutathione have been carried out, obtaining alkylated adducts (3-16) in fairly good to quantitative yields. The reaction rate and selectivity of 1 toward nitrogen and sulfur nucleophiles, in competition with the hydration reaction, have been investigated at different pH by laser flash photolysis technique. The observed reactivity spans 7 orders of magnitude on passing from water (kNu = 5.8 M-1 s-1) to the most reactive nucleophile (2.8 x 10(8) M-1 s-1, 2-mercaptoethanol under alkaline conditions). These are the first direct reaction rate measurements of nucleophilic addition to the parent o-quinone methide (1). Competition experiments provided strong kinetic support to the involvement of free 1 as an intermediate in both thermal and photochemical reactions. Furthermore, several alkylation adducts regenerate 1 either by heating (9, 10, 13, and 14) or by irradiation (9, 11-13, 16). Such a thermal and photochemical reversibility of the alkylation process opens a new perspective for the use and application of such adducts as o-QM molecular carriers.

Alkylation of amino acids and glutathione in water by o-quinone methide. Reactivity and selectivity.

Extending pKa prediction accuracy: High-throughput pKa measurements to understand pKa modulation of new chemical series

The vanadate anion in the presence of pyrazine-2-carboxylic acid (PCA ≡ pcaH) efficiently catalyzes the oxidation of 2-propanol by hydrogen peroxide to give acetone. UV−vis spectroscopic monitoring of the reaction as well as the kinetics lead to the conclusion that the crucial step of the process is the monomolecular decomposition of a diperoxovanadium(V) complex containing the pca ligand to afford the peroxyl radical, HOO• and a V(IV) derivative. The rate-limiting step in the overall process may not be this (rapid) decomposition itself but (prior to this step) the slow hydrogen transfer from a coordinated H2O2 molecule to the oxygen atom of a pca ligand at the vanadium center:  “(pca)(O)V···O2H2” → “(pca)(HO−)V−OOH”. The V(IV) derivative reacts with a new hydrogen peroxide molecule to generate the hydroxyl radical (“VIV” + H2O2 → “VV” + HO- + HO•), active in the activation of isopropanol:  HO• + Me2CH(OH) → H2O + Me2C•(OH). The reaction with an alkane, RH, in acetonitrile proceeds analogously, and in thi...

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Oxidation of 2-Propanol and Cyclohexane by the Reagent "Hydrogen Peroxide -Vanadate Anion-Pyrazine-2-carboxylic Acid": Kinetics and Mechanism †

The review deals with the most important features of phosphorus(III) derivatives, which determine their chemical properties. These are the biphilicity of the phosphorus atoms due to the presence of a free electron pair and unfilled d orbitals and the ambidentate properties of phosphorus(III) derivatives determined by the specific contribution of both nucleophilic elements (O, N, S) and elements with vacant d orbitals (Si, Sn) directly linked to the phosphorus atom. Certain limits and characteristics of this contribution have been elucidated and the mechanism of the relevant reactions has been discussed. The last section deals with the specificity of the behaviour of phosphorus(III) compounds with a phosphorus–halogen bond. The significant role of the d orbitals of the phosphorus atom in its chemical reactivity is discussed. The bibliography comprises 197 references.

https://iopscience.iop.org/article/10.1070/RC1970v039n05ABEH001993/pdf

Reactivity of Trivalent Phosphorus Derivatives

Antimicrobial activity of O,O-diethyl N-alkylaminomethyl-phosphonates and O-ethyl N-alkylaminomethylphosphonic acids

A study was made of reaction in the system: triethyl phosphite-amide (amine)-paraform(benzaldehyde). The reaction leads to the formation of the corresponding esters of aminomethyl(alkyl)phosphonic acids.

Reaction in the system trialkyl phosphite-carboxamide or secondary amine

1.

The basicity of o-aminomethylphenols in nitromethane, acetonitrile, and ethanol is lower in comparison with benzylamines, which do not have any intramolecular hydrogen bonds.




2.

The influence of the intramolecular hydrogen bond on the basicity of the o-aminomethylphenols increases in the following series of solvents: ethanol<water<acetonitrile-nitromethane.




3.

Between the values of pKa of the o-aminomethylphenols and benzylamines in water, ethanol, nitromethane, or acetonitrile, linear correlations are obtained with slopes close to unity.




4.

The relationship between pKa in nitromethane and in acetonitrile is common for primary, secondary, and tertiary alkylamines, benzylamines, o-aminomethylphenols, anilines, and pyridine.

Basicity of o-aminomethylphenols in nonaqueous media

The kinetics of the hydrolysis of di(p-nitrophenyl)methylphosphonate in aqueous solutions of triethylenetetramine and tetraethylenepentamine have been studied at various pH values. The catalytic rate constants for the neutral and monoprotonated forms of the polyamines are represented by the Bronsted equation as with the primary aliphatic amines and for the diprotonated forms they are represented together with the secondary aliphatic amines.

B. E. Ivanov

Papers

Reactivity of Trivalent Phosphorus Derivatives

Antimicrobial activity of O,O-diethyl N-alkylaminomethyl-phosphonates and O-ethyl N-alkylaminomethylphosphonic acids

Reaction in the system trialkyl phosphite-carboxamide or secondary amine

Basicity of o-aminomethylphenols in nonaqueous media

Catalysis of the hydrolysis of di(p-nitrophenyl) methylphosphonate by polyamines