Mass spectrometry of the simple N- vinylpyridinium salts

N- Vinylpyridinium halides readily undergo a Hofmann type elimination, prior to evaporation in the mass spectrometer, with formation of pyridine, acetylene and hydrogen halide as volatile products. A second important reaction is thermally induced two electron reduction of the cation to the volatile N-vinyldihydropyridine. Of minor importance is the formation of volatile compounds with the elemental composition of [cation + C₂H] and [cation + C₂H₃]. The latter is suggested to have a divinyldihydropyridine structure. Its formation is explained as due to nucleophilic attack on the cation by the N-vinyldihydropyridine present with displacement of pyridine.     

Synthesis of new v-triazolopyrimidinium salts

New v-triazolo[1,5-α]- and v-triazolo[1,5-c]pyrimidinium salts 12a-e, 13a-c have been synthesized via oxidation (i.e. cyclodehydrogenation) of the appropriate pyrimidyl ketone arylhydrazones 3a-e, 6a-c using TBB (2,4,4,6-tetrabromocyclohexa-2,5-dien-1-one) as the reagent. The arylhydrazones were obtained by standard reactions; the Grignard reaction of 2-cyano- and 4-cyanopyrimidine 1a,b, 4a-c gave 2-pyrimidyl- and 4-pyrimidyl ketones 2a-e, 5a-c , which reacted with arylhydrazines to yield the desired ketone arylhydrazones 3a-e, 6a-c.     

Synthesis of new N-quaternary-3-benzamidoquinuclidinium salts

The synthesis of racemic and enantiomerically pure N-p-methylbenzyl-3- and N-p-chlorobenzylbenzamidoquinuclidinium bromides (6-8 and 9-11, respectively) is described. These compounds were prepared from racemic or enantiomerically pure 3-benzamidoquinuclidines 3-5 using the appropriate quaternization reagents: p-methyl- benzyl bromide (1) and p-chlorobenzyl bromide (2).     

Synthesis and characterization of new triazenide salts

Stable triethylammonium triazenide salts were obtained on treatment of the appropriate triazenes with triethylamine. Those salts are described and fully characterized for the first time and are used for the preparation of alkoxycarbonylvinyltriethylammonium triazenides, which are prone to transesterification.     

Polymerization of vinylpyridinium salts. XII. Occurrence of radical polymerization in spontaneous reactions

There has been considerable disagreement regarding the mechanism of the spontaneous polymerization of vinylpyridinium salts in aqueous or acidic solution above 1.0 mol L^?1 in monomer concentration. In this report the position of Ringsdorf and co-workers is substantiated with regard to the existence of a free-radical reaction, but the kinetic results obtained differ. In particular, it is shown that a lack of spontaneous polymerization below 1.0 mol L^?1 is not due to a nonexistence of-a critical monomer concentration for aggregation, but is instead a kinetic phenomenon of R_p ～ [M]^2.7.     

Synthesis of new condensed analogs of isoindolinium salts

Quaternary ammonium salts that contain a 3-(-naphthyl)propargyl group in addition to a group of the propargyl type undergo intramolecular cyclization of the diene-synthesis type under base-catalysis conditions to give condensed isoindolinium analogs.Communication 209 from the series Research on amines and ammonium compounds. See [1] for Communication 208.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 759–762, June, 1991.     

几种新的3,7-二取代二苯并五元环状溴嗡盐的合成

4,4'-二硝基联苯在浓硫酸中与溴化钠及过硫酸钾反应,直接生成3,7-二硝基二苯并溴五环盐(5).5经SnCI~2-HCI还原得到3,7-二氨基二苯并溴五环盐(6),由6制得重氮盐溶液分别与氯化亚铜,溴化亚铜及碘化钾反应得到3,7-二氯二苯并溴五环盐(7),3,7-二溴二苯并溴五环盐(8)及3,7-二碘二苯并溴五环盐(9).5-9均匀新化合物,其结构经^1HNMR.MS.IR证实.     

Synthesis of new spiropyrans based on 2,3-cycloalkenobenzopyrylium salts

A method is described for the synthesis of spiropyrans from 2,3-cycloalkenobenzopyrylium salts and hydroxyaldehydes with subsequent treatment of the-styryl derivatives with ammonia in ether.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1313–1315, October, 1970.     

Synthesis and X-ray study of new columnar heteroaromatic salts

The synthesis of 2,4,6-triarylpyrylium tetrafluoroborates substituted by six long alkyloxy chains (n = 8 and 12) is described. These salts exhibit a discotic mesophase from room temperature to 200°C. X-ray diffraction experiments on powder and oriented samples show that this phase is an ordered hexagonal columnar phase, D_ho.     

Synthesis of new spiropyrans from 2,5-dimethyl-1,3-benzodithiolium salts

New spiropyrans that have thermochromic properties were obtained by the condensation of 2,5-diniethyl-1,3-benzodlthiolium perchlorate with o-hydroxy aromatic aldehydes and subsequent treatment of the resulting 2-styryl derivatives with ammonia in ether.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 318–320, March, 1972.     

Synthesis and inhibiting capacity of new fluorine-containing quaternary ammonium salts

New fluorine-containing quaternary ammonium salts exhibiting a high inhibiting capacity against hydrochloric acid corrosion of low-carbon steels were synthesized. The polarization resistance method was used to determine the uniform-corrosion rates of steel-3 and steel-35 in relation to the structure of fluorine-containing moieties of quaternary ammonium salts and their concentration.     

Reactions with heterocyclic diazonium salts. Synthesis of several new azolylhydrazones

Several new stable azolylhydrazones could be synthesized via coupling of diazotised cycliuc amidines with active methylene reagents. The obtained compounds were utilised for synthesis of several, otherwise not readily accessible fused azoles.     

Polymerization of vinylpyridinium salts. III. Further studies on the interfacial and isotropic polymerization of 4-vinyl-N-methylpyridinium methylsulfate

In the present study the polymerization of 4-vinyl-N-methylpyridinium methylsulfate at liquid–liquid interfaces is investigated. Various experimental procedures that may favor the interfacial mode of polymerization over the isotropic one are discussed. The effectiveness of the methods was evaluated by physical characterization studies and particularly polymer tacticity. This last property is directly associated with the achieved organization of the monomers at interfaces. ¹³C-NMR technique was used for tacticity determination. According to tacticity, random polymers are primarily obtained that result from an isotropic polymerization in the aqueous phase, where the monomer is extremely soluble. The small predominance of the syndiotactic triad over the isotactic one is explained by the occurrence of an interfacial polymerization induced by the orientation of the monomers. A polymerization model is proposed that justifies the stereospecificity modification of polymerization.     

Synthesis of N-methylpentafluorophenylpyridinium salts

Di- and triaryl-N-methylpyridinium perchlorates bearing pentafluorophenyl groups have been obtained by reaction of the appropriate pyrylium salts with methylamine. In the case of 4-phenyl-2,6-bis(pentafluorophenyl)pyrylium perchlorate, a stable 2H-pyran intermediate was isolated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1100–1103, August, 1991.     

Synthesis of sym-octahydroacridinium salts

The synthesis of sym-octahydroacridine from cyclohexanone, formaldehyde, and ammonium acetate at 180–200°C in 5% yield is known [1].     

Synthesis of N-tetrahydropyranyl-S-methylmethioninesulfonium salts

D,L-Methionine reacts in alkaline medium with 4-methyl-3,4-epoxytetrahydropyran via the amino group to form, in accordance with the Krasusskii rule, an oxirane ring opening product, namely N-(4-hydroxy-4-methyl-3-tetrahydropyranyl)-D,L-methionine. N-(4-Hydroxy-4-methyl-3-tetrahydropyranyl)-S-methylmethioninesulfonium salts are synthesized in high yields by methylating the latter then treating it with organic or inorganic acids.Bashkir State University, Ufa. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 597–600, May, 1994. Original article submitted February 10, 1994.