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Lactic acid bacteria displaying increased ability to produce lactic acid, medium proteolytic activity, and tolerance to osmotic stress were isolated under selective conditions from phyllosphere and rhizosphere of registered and raised cultivars of legumes. Lactic fermentation of poorly ensilable leguminous plants (red clover and Caucasian goat’s rue) was performed by introduction of rifampin-resistant homofermenting representatives of the genus Lactobacillus (selected according to a set of technologically important characteristics). The results demonstrate that introduction of active local strains of lactobacteria, as well as the collection strain Lactobacillus plantarum BS933, enhances activation of ensiling and increases the quality of fodder, as assessed according to the standard criteria (a decrease in pH of the medium, the ratio of lactic acid to fatty acid homologues, and the composition of silage microflora).

Lactic acid bacteria displaying increased ability to produce lactic acid, medium proteolytic activity, and tolerance to osmotic stress were isolated under selective conditions from phyllosphere and rhizosphere of registered and raised cultivars of legumes. Lactic fermentation of poorly ensilable leguminous plants (red clover and Caucasian goat's rue) was performed by introduction of rifampin-resistant homofermenting representatives of the genus Lactobacillus (selected according to a set of technologically important characteristics). The results demonstrate that introduction of active local strains of lactobacteria, as well as the collection strain Lactobacillus plantarum BS 933, enhances activation of ensiling and increases the quality of fodder, as assessed according to the standard criteria (a decrease in pH of the medium, the ratio of lactic acid to fatty acid homologues, and the composition of silage microflora).

The reactions of P4/propylene oxide/Me3N/HX (mole ratio=1∶5∶0.8∶1) leads to the formation of an oligomer. The chain of this oligomer features the sequence of -C-P(O)-O-fragments. Features were determined which control the rate of P4 conversion depending on the composition of the reaction mixture. The oligomer composition was determined.

1. Thermodynamic equilibrium between the conformers is realized in trialkyl phosphates [except tri(tert-butyl) phosphate]. The conformer with the cisoid or gauche arrangement of all the OR groups in relation to the P=O bond predominates. 2. In tri(tert-butyl) phosphate the gauche-gauche conformer is fully stabilized. 3. Increase in the volume of R leads to displacement of the form with the trans orientation of one of the OR groups from the conformational equilibrium.

1. The 2,2′-diethyl- and 2,2′-diphenylphosphon-2,2′-azopropanes undergo thermal homolysis with simultaneous rupture of both of the C-N bonds. 2. Study of the kinetics of the thermal homolysis of the substituted 2,2′-azopropanes gives a basis for determination of the energy of radical stabilization by the substituent. 3. The energy of isopropyl radical stabilization by a P(0) (OR)2 type substituent adjacent to the radical center is some 5 kcal/mole. 4. The ability of the substrate to enter into homolytic addition, displacement, and dissociation depends, in the first instance, on the energy of substituent stabilization of the product radical center, the sensitivity of the substrate to this substituent effect in any one series of reactions increasing with an increase in the activation enthalpy and entropy and the displacement of the transition state along the reaction coordinate.

On the basis of a study of the reaction of triethyl phosphite with o-hydroxybenzyl alcohol by methods of IR and NMR spectroscopy and the kinetic data, it was established that the reaction is first order and proceeds according to the classical scheme of the Arbuzov rearrangement, with intermediate formation of a quasiphosphonium-type complex.

Bei der Umsetzung des Diethyl-phenyl-phosphits (I) mit dem Nitropropen (II) entstehen die Substanzen (III)-(V) im Verhaltnis 31:36i33, deren Bildungsweisen eingehend diskutiert werden.

Bei der Umsetzung von (I) mit (II) entstehen eine Vielzahl von Verbindungen, die sich mit Hilfe der Kemresonanzund Protonenresonanzspektroskopie und Gasflussigchromatographie identifizieren und quantitativ erfassen lassen.

T e r t i a r y alkyl halides usual ly do not en te r into the Arbuzov and Michaelis B e c k e r reac t ions , but the exceeding ease of uucleophilic SN1 substi tut ion in a , c~Y-dichloroazoalkanes [1] gave reason to expect that these halo der iva t ives will r e ac t with phosphites. Never the less , in var ious iner t solvents and also without a solvent, at t e m p e r a t u r e s up to 120 ~ the compounds (CH30)3P, (C2H50)3P , (C2HsO)2PONa , and (i-C3HTO)2PONa failed to r eac t with 2 ,2 ' d i ch lo ro -2 ,T -azop ropane (I). In the p resence of AcOH (0.045 mole) , 2 ,2 ' -d ie thylphosphono-2 ,2 ' -azopropane is formed in 60% yield f rom 0.03 mole of t r ie thyl phosphite and 0.015 mole of (I) (3 h, 70-80~ Af te r chromatographing on s i l ica gel (benzene a l c o h o l a c e t o n e , 15 : 2 : 1) we obtained a pale liquid, n~ 1.4489; d 2~ 1.0969; Rf 0.4 (Silufol, the mobile phase is indicated above); 631p -25 ppm (phosphonate). NMR spec t rum (in CCI 4, 5, ppm): 1.42 d (J(CHz)2CP = 22.4 Hz), 1.35 t

For the mixed esters of tetracoordinated phosphorus acids, that contain POAlk and PSAlk groups, a cleavage of the ester and thioester bonds at a commensurate rate is observed in the reaction with water and during acid hydrolysis, in contrast to alkaline hydrolysis, which leads to a preferential cleavage of the P-S bond.

Organophosphorus polyols may be obtained by the reaction of elemental phosphorus with propylene oxide initiated by trivalent phosphorus derivatives.

T e r t i a r y alkyl halides usual ly do not en te r into the Arbuzov and Michaelis B e c k e r reac t ions , but the exceeding ease of uucleophilic SN1 substi tut ion in a , c~Y-dichloroazoalkanes [1] gave reason to expect that these halo der iva t ives will r e ac t with phosphites. Never the less , in var ious iner t solvents and also without a solvent, at t e m p e r a t u r e s up to 120 ~ the compounds (CH30)3P, (C2H50)3P , (C2HsO)2PONa , and (i-C3HTO)2PONa failed to r eac t with 2 ,2 ' d i ch lo ro -2 ,T -azop ropane (I). In the p resence of AcOH (0.045 mole) , 2 ,2 ' -d ie thylphosphono-2 ,2 ' -azopropane is formed in 60% yield f rom 0.03 mole of t r ie thyl phosphite and 0.015 mole of (I) (3 h, 70-80~ Af te r chromatographing on s i l ica gel (benzene a l c o h o l a c e t o n e , 15 : 2 : 1) we obtained a pale liquid, n~ 1.4489; d 2~ 1.0969; Rf 0.4 (Silufol, the mobile phase is indicated above); 631p -25 ppm (phosphonate). NMR spec t rum (in CCI 4, 5, ppm): 1.42 d (J(CHz)2CP = 22.4 Hz), 1.35 t