A. I. Alekhina

Reaction of dialkylphosphites with N-alkyl-2-chloraldimines

Reactions of some dialkylphosphorous acids with the N-substituted 2-chloroimines were studied. It was shown that the nature of substituents at the nitrogen and phosphorus atoms in the starting materials affected the structure of the reaction products.

Reaction of dialkyl phosphites with N-2-methyl-2-chloropropylidenealkylamines

Organophosphorus compounds (OPCs) contain� ing aminoalkylphosphoryl fragments are of large prac� tical and theoretical interest. These compounds show a wide spectrum of useful properties. The addition of dialkyl phosphites to imines is one of the main meth� ods for the preparation of aminoalkylphosphonates. We have shown recently (1) that 2�halosubstituted alkylpropylidenamines react with dialkyl phosphites to form new types of OPCs, along with addition prod� ucts. It was found that the structure of final products is dependent on the halogen nature. To reveal the effect of the nature of substituents at P(IV) and N(III) on the structure of resulting products and the synthesis of polyfunctional OPCs of new types, we have studied the reactions of dimethyl, diethyl, diisopropyl, dinbutyl�, and di�2�chloroet� hyl phosphites (I) with (2�chloropropylidene)alkyl� amines ( II) containing tertbutyl, benzyl, and isopro� pyl substituents at the nitrogen atom. The reaction of dialkyl phosphites I with com� pounds II leads to the initial formation of addition products showing phosphorus resonance signals at 26-29 ppm. Addition product III with R 2 = tB u and R 1 = Me is a crystalline solid and can be stored in the pure state for a long time without change. When the reaction mixture was stored for 15- 20 days, the primary addition products undergo fur� ther transformations and the structure of the reaction products depends on the nature of the substituents at P(IV) and N(III). Thus, the ease of the transformation and the structure of the products are dependent on the nature of the substituents at N(III): if R 2 = iPr and Bz, further transformation of the addition product proceeds much more readily as compared with the compound with R 2 = tB u. It is likely that cyclic inter� mediate IV in the case of R 2 = tB u is more difficult to form as compared with R 2 = iPr and Bz on account of

Synthesis and properties of O,O-dialkyl [1-hydroxy-3-(dialkylamino)-2,2-dimethylpropyl]phosphonates

O,O-Dialkyl [1-hydroxy-3-(dialkylamino)-2,2-dimethylpropyl]phosphonates were prepared for the first time. By means of NMR 1H, IR spectroscopy and quantum-chemical calculations the presence in them of various H-bonds was established. In the crystalline state P=O…HO intermolecular hydrogen bonds favor the formation of cyclic dimer associates DP=O. In the liquid state and concentrated solutions P=O…HO and N…HO intermolecular hydrogen bonds cause the formation of cyclic dimer associates DP=O and DN, and intramolecular hydrogen bonds provide the existence of different conformations of the monomer form MN, the most stable among them with the non-strained six-membered …NCCCOH… ring.

Reaction of 3-(dimethylamino)-2,2-dimethylpropanal with trialkylphosphites in the presence of acetic anhydride

Hitherto the functionally substituted aldehydes were not introduced into the new version of the Birum reaction. We first used the readily accessible 3-(dimethylamino)-2,2-dimethylpropanal in this reaction. This choice was dictated by the fact that, firstly, the presence of pharmacophore amine group can lead to the synthesis of new types of multifunctional organophosphorus compounds possessing potential biological activity. Secondly, the new reaction routes can be realized under the influence of the three-coordinated nitrogen atom. An equimolar mixture of trialkylphosphite I, 3-(dialkylamino)aldehyde II, and acetic anhydride III was kept at room temperature for 1 month. After every week we registered the H NMR spectrum of the reaction mixture and observed a gradual decrease in the signal intensity of the aldehyde group proton (δ 10 ppm). The signal intensity of methine proton of the reaction products IV and VI increases at δ 6.5 and 5.2 ppm. After one month the intensity of these signals ceased to change, although the P NMR spectrum of the reaction mixture indicates a substantial amount of the starting trialkylphosphite I. The main reason of this is the consumption of reagents II and III in the formation of the non-phosphorus product VI. DOI: 10.1134/S1070363211070309