Substituted 2-methyl- and 2-methyleneindolines. 2. Nitro- and amino-substituted 2-methyl- and 2-methylene-indolines

From 5- and 6-aminotetramethylindolines, 2-methyleneindolines have been synthesized; these compounds can be condensed with other heterocyclic systems. The nitration of 1,2,3,3-tetramethylindoline under different conditions was studied.For communication 1, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 919–923, July, 1989.     

Pyrimidones. 2. Synthesis and reactions of 2-chloropyrimidines

The treatment of 1-alkyl-5-aryl and 1-alkyl-4,5-diaryl-2-(1H)pyrimidones with phosphorus oxychloride and phosphorus pentachloride resulted in chlorination and dealkylation to furnish 2-chloro-5-aryl (or 4,5-diaryl)-pyrimidines. These chlorpyrimidines were reacted with a variety of nitrogen, oxygen, sulfur, and carbon nucleophiles to produce the corresponding 2-substituted pyrimidines. In the case of phenyllithium, attack occurred at the 4-position of the pyrimidine ring yielding 11 . Triazolopyrimidine 9 was synthesized via the treatment of 2d with hydrazine followed by reaction with triethyl orthoformate.     

Antiandrogen. I. 2-azapregnane and 2-oxapregnane steroids.

2-Azachlormadinone acetate (5a, 17-acetoxy-6-chloro-2-azapregna-4,6-diene- 3,20-dione), 2-oxachlormadinone acetate (6, 17-acetoxy-6-chloro-2-oxapregna-4,6-diene-3,20-dione) and the derivatives were prepared as potential antiandrogenic agents. Biological evaluation showed that 5a and 6 had a potent antiandrogenic activity when tested in the castrated male rat.     

2-Amino-2-thiazoline. V. phenylthioureido and phenylureido derivatives of 2-thiazoline

The reaction of 2-amino-2-thiazoline (I) with phenylisothiocyanate has been reported to give 2-imino-3-phenylthiocarbamoylthiazolidine (II) at low temperatures and l-phenyl-3-(2-thiazolin-2-yl)-2-thiourea (III) at ca. 100°. When performed by us, however, this reaction gave only a single mono-adduct regardless of the temperature. Nmr and chemical evidence indicates that structure III is the correct one. Treatment of I with phenylisocyanate also gave a mono-adduct which was established to be l-phenyl-3-(2-thiazolin-2-yl)urea (V). Compound I does not form a simple di-adduct with excess phenylisothiocyanate but does so with phenylisocyanate to give 2-phenylcarbamoylimino-3-phenylcarbamoylthiazolidine (VI). The reaction of III with phenylisocyanate gives 2-phenylthiocarbamoylimino-3-phenylcarbamoylthiazolidine (VII), however, the corresponding reaction of V with phenylisothiocyanate does not give the anticipated product but a mixture of compounds which includes VI and VII.     

Diazines. IX. Metalation of 2-chloro, 2-methoxy and 2-pivaloylaminoquinoxaline

The lithiation of 2-chloro, 2-methoxy and 2-pivaloylaminoquinoxaline was studied. In the case of 2-chloro and 2-methoxyquinoxaline the simultaneous formation of dimers could not be avoided. The resulting lithio derivatives were reacted with carbonyl compounds and iodine. Yields in excess of 50% were obtained.     

2-Polyfluoroalkylchromones. 5. Nitration and chlorination of 2-trifluoromethylchromones

Electrophilic nitration of 2-trifluoromethylchromone and its 6- and 7-methoxy derivatives affords 6-, 5-, and 8-nitro derivatives, respectively, while 5,7-dimethyl-2-trifluoromethylchromone yields a 6,8-dinitro derivative. Radical chlorination results in 3-chloro derivatives.     

An Ab Initio Study of C2H2.H2, C2H2.N2, and C2H2.Ar Complexes

Ab initio calculations at the post Hartree–Fock level were performed on complexes of acetylene with hydrogen, nitrogen, and argon. Total energies, optimum geometries, and binding energies were calculated, using the 6-311G** and the 6-31+G(2df,2pd) basis sets. Calculations showed the complexes to be more stable than the separate entities, with the exception of the acetylene–hydrogen complex.     

2-Polyfluoroalkylchromones. 7. Reactions of 6-substituted 2-tetra- and 2-pentafluoroethylchromones with 2-aminoethanol

The reactions of 2-aminoethanol with 6-methyl-2-tetra- and 6-methyl-2-pentafluoroethylchromones involve the carbonyl group to give imines; the reactions with 6-nitro-2-tetra- and 6-nitro-2-pentafluoroethylchromones involve the C(2) atom, resulting in the pyrone ring opening. This also occurs in the reactions of 2-(1,1,2,2-tetrafluoroethyl)chromone with ammonia and benzylamine.     

Substituted 2-methyl- and 2-methyleneindolines. 3. Nitroamino-5,6-disubstituted 2-methyl- and 2-methyleneindolines

A method is developed for the synthesis of 5,6-disubstituted nitroamino- and nitromethylamino-2-methyl- and-2-methyleneindolines. These are starting compounds for the synthesis of 2-methyleneindolines condensed with some heterocycle.See [1] for Communication 2.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1495–1499, November, 1990.     

Hybrid fluorocarbon-hydrocarbon CO2-philic surfactants. 2. formation and properties of water-in-CO2 microemulsions

Hybrid fluorocarbon-hydrocarbon (F-H) sulfate surfactants are shown to be efficient stabilizers in water-in-CO2 (w/c) microemulsions. The chain structure and F-H ratio affect the regions of P-T phase stability and aggregation structure in these w/c phases. High-pressure near-infrared spectroscopy and small-angle neutron scattering measurements of microemulsified water provide evidence for the stabilization of w/c microemulsion droplets. The relative lengths of the two chains were found to influence the favored aggregation structure: for symmetric chain surfactants (F8H8, F7H7) spherical reverse micelles are present, but for asymmetric chain surfactants (F7H4, F8H4) extended cylinder aggregates form. These changes in aggregation are consistent with different surfactant packing parameters owing to the controlled variations in molecular structure. Furthermore, the general order of w/c phase transition pressures (F8H8 < F7H7 and F8H4 < F7H4) is in line with estimations of surfactant fractional free volume, as proposed by Johnston et al. (J. Phys. Chem. B 2004, 108, 1962-1966). Studies of adsorption at the poly(dimethylsiloxane)-water interface are shown to be valuable for assessing the CO2-philicity of new surfactants. All in all, the symmetric F8H8 and F7H7 analogues are seen to be the most efficient compounds from this class for applications in CO2.     

Substituted 2-methyl- and 2-methyleneindolines. 6. Adducts of dialkylphosphites with 1,3,3-trimethyl-2-methyleneindoline. Reagents for synthesizing 5-substituted 2-methyl- and 2-methyleneindolines

The readily formed addition products of dialkylphosphites and 1,3,3-trimethyl-2-methyleneindoline have been used to synthesize 1,2,3,3-tetramethyl-3H-indolium salts and their derivatives substituted in the benzene ring. In most cases the protecting phosphorus group can be readily removed by adding mineral acids.For Communication 5, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1049–1054, August, 1993.     

1,3-thiazepines. 2. Reaction of 2-iminohexahydrothiazepines with phenylisocyanate and isothiocyanates

We have shown that as a result of reaction of phenylisocyanate with 2-benzyl- and 2-aryliminohexahydrothiazepines, the corresponding N-substituted N-tetrahydroazepinyl-N-phenylureas are formed. In the case of isothiocyanates, on boiling in different solvents we obtained the products of the exchange reaction; and at room temperature, we also obtained substituted thioureas. We suggest a probable scheme for the process.For communication 1, see [1].Institute of Phytochemistry, Academy of Sciences of the Uzbekistan Republic, Tashkent 700170. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 416–422, March, 1997.     

Oxidation of ethyne and But-2-yne. 2. Master equation simulations

The aim of this study is to improve understanding of the tropospheric oxidation of ethyne (acetylene, C2H2) and but-2-yne, which takes place in the presence of HO and O2. The details of the potential energy hypersurface have been discussed in a previous article [Maranzana et al., J. Phys. Chem. A 2008, 112, XXXX]. For both molecules, the initial addition of HO radical to the triple bond is followed by addition of O2 to form peroxyl radicals. In both reaction systems, the peroxyl radicals take two isomeric forms, E1 and E2 for ethyne and e1 and e2 for but-2-yne. Energy transfer parameters (alpha = 250 cm-1) for the ethyne system were obtained by simulating laboratory data for N2 buffer gas, where O2 was not present. In simulations of C2H2 + HO when O2 is present, E1 reacts completely and E2 reacts almost completely, before thermalization. Radical E1 produces formic acid ( approximately 44%) and E2 gives glyoxal ( approximately 53%), in quite good agreement with experiments. For but-2-yne, pressure-dependent laboratory data are too scarce to obtain energy transfer parameters directly, so simulations were carried out for a range of values: alpha = 200-900 cm-1. Excellent agreement with the available experimental yields at atmospheric pressure was obtained with alpha = 900 cm-1. Two reaction channels are responsible for acetic acid formation, but one is clearly dominant. Biacetyl is produced by reactions of e1 and, to a minor extent, e2. The peroxyl radical e2 leads to less than 8% of all products. Vinoxyl radical (which has been reported in experiments involving C2H2 + HO) and products of its reactions are predicted to be negligible under atmospheric conditions.     

2-Polyfluoroalkylchromones. 13. Synthesis and nitration of 6,8-dibromo-2-trifluoromethylchromone

The nitration of 6,8-dibromo-2-trifluoromethylchromone depends on the reaction conditions and affords 6,8-dibromo-5-nitro- or 3,6,8-tribromo-5-nitro-2-trifluoromethylchromones. The structures of these compounds were determined from the ¹H and ¹³C NMR spectroscopic data.     

Polymerization of 2-Oxazolines. IV. The Structure and the Reactivity of 2-Substituted-2-oxazolines and Oxazolinium Perchlorates

Abstract

In order to elucidate the structure and the stability of the growing cationic end in the polymerization of 2-oxazolines, the reactions of 2-bromoethylbenzamide with silver salts such as silver perchlorate, tetrafluoroborate, nitrate, nitrite, cyanate, and acetate were investigated. The reactions with silver perchlorate and tetrafluoroborate gave the 2-phenyl-2-oxazolinium salt (intramolecular O-alkylation product) quantitatively, whereas the reaction with silver nitrate gave the corresponding alkyl nitrate (staight-chain product). For the reactions with silver nitrite, cyanate and acetate, both products were obtained. In order to elucidate the ring-opening reactivity of the oxazolinium cation, the ring-opening addition reaction of N-methyl-2-oxazolinium perchlorates with pyridine was investigated. It was found that N-methyl-2-phenyl-2-oxazolinium perchlorate was more reactive toward the nucleophilic ring-opening reaction than was N-methyl-2-methyl-2-oxazolinium perchlorate. The mutual copolymerization of 2-phenyl-2-oxazoline with the other 2-substituted-2-oxazoline such as 2-methyl-, 2-isopropyl-, and 2-benzyl-2-oxazoline indicated that the monomer reactivity ratio r₂ was much larger than unity, whereas r₁ was very much smaller. Based on these results, the influence of the structure and the reactivity of the monomer and the growing cationic end of the polymerizability of 2-oxazolines are discussed.     

Mass spectrometeric study of thiocarbamoyl-substituted 2-aminothiazoles and 2-iminothiazolines. 2. N-thiazolyl- and N-thiazolinylidene-N′-peracetyl glycosylthioureas

The mass spectra of isomeric peracetylated glycosides, substituted in the C₍₁₎-position with thiazolyl and thiazolinylidene thioureido groups, reveal qualitative and quantitative differences in the processes associated with elimination of fragments containing the thioureido functional group. We have studied, in addition to cleavage of the acetoxy groups in the glycosidic units, the fragmentation processes of the carbohydrate unit.Communication 1, see [1]Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1539–1543, November, 1989.     

2'-C-branched ribonucleosides. 2. Synthesis of 2'-C-beta-trifluoromethyl pyrimidine ribonucleosides

[structure: see text]. The first synthesis of 2'-C-beta-trifluoromethyl pyrimidine ribonucleosides is described. 1,2,3,5-Tetra-O-benzoyl-2-C-beta-trifluoromethyl-alpha-D-ribofuranose (3) is prepared from 1,3,5-tri-O-benzoyl-alpha-D-ribofuranose (1) in three steps and converted to 3,5-di-O-benzoyl-2-C-beta-trifluoromethyl-alpha-D-1-ribofuranosyl bromide (5). The 1-bromo derivative (5) is found to be a powerful reaction intermediate for the synthesis of ribonucleosides. The reaction of silylated pyrimidines with (5) in the presence of HgO/HgBr2 affords exclusively the beta-anomers (6-8). Deprotection of (6-8) with ammonia in methanol yields the 2'-C-beta-trifluoromethyl nucleosides (9-11).     

Thermodynamic and spectroscopic properties of 2-pyrrolidinones. 2. Dielectric properties of 2-pyrrolidinone in binary mixtures

Dielectric permittivities of 2-pyrrolidinone - acetone, -dimethyl sulfoxide,-2-propanol, -dichloromethane and -water systems were measured as a function of mole fraction over the whole composition range at 30 and 50°C. The excess dielectric permittivities are predominantly negative for all the mixtures and the excess molar polarizations are negative except for 2-pyrrolidinone - water and 2-pyrrolidinone - dimethyl sulfoxide mixtures. The large negative excess quantities are indicative of the strong specific interactions between the like and unlike components of the solution mixtures.