Synthesis of 2-amino-1-azirines and their reactions with carboxylic acids

A method was developed for the synthesis of 2-amino-1-azirines under the conditions of a modified Neber reaction. Their reactivities with respect to mono- and dicarboxylic acids and thiocarboxylic acids were investigated.Translated from Khimiya Geterotsiklieheskikh Soedinenii, No. 9, pp. 1202–1206, September, 1985.     

The vibrational,electronic, and mass spectra of 2-amino-1-azirines

It is shown by IR, UV, and mass spectroscopy that the 2-amino-3-arylcarbamoyl-1-azirines, first represented as three-membered, cyclic amidines containing a primary amino group and able to undergo a prototropic rearrangement, exist exclusively in the aminoaziridine form.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 44–48, January, 1987.     

Studies on synthetic approaches to 1H- and 2H-indazolyl derivatives

Synthetic approaches designed to provide 1H- and 2H-indazolyl derivatives of potential biological interest are reported. Special emphasis has been placed on the characterization of indazolylpyridinium products generated from reactions between indazole and 4-chloro-1-methylpyridinium iodide under various conditions. A stable mixture consisting of 3 parts of the 1H-isomer 9 to 1 part of the 2H-isomer 10 was obtained at room temperature in the presence of the base 2,2,6,6-tetramethylpiperidine (TMP). The same reaction at 60 degrees C gave only the 1H-isomer 9. At 100 degrees C in the absence of TMP only the 2H-isomer 10 was formed. The isomerization of 10 to 9 was found to proceed quantitatively at 60 degrees C but only in the presence of TMP. The effects of temperature and base on the course of these reactions are rationalized in terms of kinetic and thermodynamic parameters.     

New reactivity of 1-(2-pyridyl)-2-propen-1-ol with nitro derivatives

1-(2-Pyridyl)-2-propen-1-ol showed an unprecedented reactivity behaving as Hantzsch ester 1,4-dihydropyridine mimic for the metal-free reduction of the nitro group of electron-deficient aromatic and heteroaromatic nitro compounds to the corresponding amino function. The redox mechanism is part of a domino process involving a direct trapping of the amino derivatives through aza-Michael addition to the vinyl ketone intermediate leading to the one-pot formation of new functionalised aminoacylpyridines.     

Cycloaddition reaction of 2-vinylazetidines with benzyne: a facile access to 1-benzazocine derivatives

The cycloaddition reaction of 2-vinylazetidines with benzyne proceeded smoothly without a catalyst, and various benzazocine derivatives were isolated in good to high yields. The scope of the reaction, as well as the reactions of other arynes, has been studied.     

An unexpected reaction of 2-vinyloxyethyl isothiocyanate with halocarboxylic acids

Reactions of 2-vinyloxyethyl isothiocyanate with aliphatic halocarboxylic acids give rise to their 1-(2-isothiocyanatoethoxy)ethyl esters in quantitative yields. An unusual rearrangement of 1-(2-isothiocyanatoethoxy)ethyl chloro(bromo)acetate and 3-bromopropanoate to 5-aza-7-chloro(bromo)-4-oxo-3-thiaheptanoic and to 6-aza-8-bromo-5-oxo-4-thiaoctanoic acids, respectively, was observed. Monohalocarboxylic acids and their esters were shown to readily alkylate l,3-oxazolidine-2-thione to form the same thiaheptanoic and thiaoctanoic acids and their esters.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 350–354, February, 1993.     

A rare case of three rearrangements during the cycloaddition-elimination reaction of 4-methyl-5-phenylimino-Δ2-1,2,3,4-thiatriazoline with 2-pyridyl isothiocyanate

2-Pyridyl isothiocyanate ( 7 ), with its electrophilic and basic properties, gives a series of ring-transformation reactions with 4-methyl-5-phenylimino-1,2,3,4-thiatriazoline ( 1 ) at 60°. Two dithiazolidines, 8 and 10 , are formed as major products at an early stage of the reaction, whereas two thiadiazolidines, 9 and 11 , predominate at the end. The mechanism (Schemes II and III) has been elucidated by following the reaction course under a variety of conditions and by analyzing the products by ¹³C nmr spectroscopy.     

The reaction of 2-iminobenzimidazoline derivatives with chlorosulfuric acid

The reaction of 2-imino-1,3-dimethylbenzimidazoline and its N-substituted derivatives with chlorosulfuric acid is examined. It is shown that the reaction leads to the formation of the sulfonic acid in those cases where the hydrogen of the NH group is unsubstituted, or where the substituent possesses an electron-donor character. Sulfonyl chlorides are obtained only when the exocyclic nitrogen atom bears an electrophilic radical, which reduces the basicity of the guanidine moiety.     

Unexpected result of the reaction of 2-vinyloxyethyl isothiocyanate with bromoacetic acid

2- [1-(Bromoacetoxy)ethoxy]ethyl isothiocyanate (II) (BrCH₂CO₂CH(CH₃)OCH₂CH₂. N-C-S) was found to be an adduct of 2-vinyloxyethyl isothiocyanate (I) with bromoacetic acid. Upon storage, (II) rearranges to previously unreported 1-bromo-3-aza-4-oxo-5-thiaheptanoic acid (III) (BrCH₂CH₂NHC(O)CH₂C0₂H).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2370–2372, October, 1991.     

2-isoxazoline derivatives—VIII : The reaction of nitrile oxides with tropone

The reaction of nitrile oxides with tropone yields a mixture of at least 8 products, the structures of which are based on spectral and chemical evidence. Both addition of the 1,3-dipole to the carbonyl group and cycloadditions to the CC double bonds system have been observed. Peri-, regio- and stereo-selectivity of the 1,3-dipole cycloaddition are discussed and rationalized on the basis of simple perturbation theory approach.     

The reaction products of 2H-isoindole-4,7-dione derivatives with 2-aminobenzenethiol

From 2,3,4-Trisubstituted oxazolium-5-oxides and 2-methyl-, 2-phenyl- or 2-bromo-1,4-benzoquinone 1,2,3,5-tetrasubstituted 2H-isoindole-4,7-dione derivatives were prepared. These compounds were condensed with 2-aminobenzenethiol to produce 1,2,3-trisubstituted or 1,2,3,5-tetrasubstituted 4H-pyrrolo[3,4-a]phenothiazin-4-one derivatives. In the case of 1,2,3-trisubstituted 5-methyl-2H-isoindole-4,7-dione 1,2,3,5-tetrasubstituted 7-(2-mercaptophenyl)imino-2H-isoindole-4-one was obtained instead of the expected phenothiazinones.     

Perfluoro-1-(butylimino)butyl isothiocyanate. Synthesis and reaction with n-propylamine

The reaction of perfluoro-5-azanon-4-ene with KSCN in an aprotic dipolar solvent provides perfluoro-1-(butylimino)butyl isothiocyanate. The latter was reacted with n-propylamine in the presence of triethylamine to obtain fluoro-substituted derivatives of thiourea, heptafluoropropionic acid, and 1,3,5-thiadiazine.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 10, 2004, pp. 1655–1658.Original Russian Text Copyright © 2004 by Furin, Zhuzhgov.This revised version was published online in April 2005 with a corrected cover date.     

新型1-吡啶基-3,5-二甲基-1-氢吡唑类化合物的合成及晶体结构

以卤代吡啶为起始原料与水合肼反应合成肼基吡啶衍生物中间体,该中间体进一步与2,4-戊二酮关环合成了一类新型1-吡啶基-3,5-二甲基吡唑衍生物。对合成目标化合物进行了质谱、核磁表征。并且采用X射线单晶衍射分析方法进一步测定了目标化合物1-(3,5,6-三氯吡啶-2-基)-3,5-二甲基-1氢吡唑(3f)的晶体结构。     

Synthesis of 5-dialkylamino-1,2,3-triazoles and 2-amino-1-azirines from tertiary amides

The reaction of sodium azide with β-monosubstituted-α-chloroenamines (generated from tertiary amides) yields either 5-dialkylamino-1,2,3-triazoles or 2-amino-1-azirines according to the basicity of the amine substituent.     

Synthesis of 4,5-dihydrothiazole derivatives by the reaction of perfluoro-2-methylpent-2-en-3-yl isothiocyanate with ambident N,O- and N,S-nucleophiles

The reactions of perfluoro-2-methylpent-2-en-3-yl isothiocyanate with ambident N,O- and N,S-nucleophiles (thiazole-2-thione, pyridine-2-thione, 2-hydroxypyridine, benzothiazole-2-thione, benzoxazole-2-thione, 3,4,5,6-tetrahydropyrimidine-2-thione) in the presence of triethylamine yield only 2-N-substituted 4,5-dihydrothiazole derivatives. The molecular structures of three products were determined by X-ray diffraction analysis. The reaction pathways are discussed.     

1-(偶氮苯基)-3-(3,5-二溴-2-吡啶)-三氮烯的合成及其与镉的显色反应

报道了 1 (偶氮苯基 ) 3 ( 3,5 二溴 2 吡啶 ) 三氮烯的合成及其与镉的显色反应。在TritonX 1 0 0存在下 ,于pH 1 0 .9的Na2 B4O7 NaOH缓冲介质中 ,镉与ABDBPDT形成摩尔比 1∶3型红色配合物。试剂及配合物的最大吸收波长分别为 430nm和 5 30nm。表观摩尔吸光系数为 1 .75× 1 0 5L·mol- 1 ·cm- 1 。镉含量在 0 μg/2 5mL～ 1 2 μg/2 5mL范围内符合比耳定律     

Fluorine-containing heterocycles: XVI. Reactions of tetrafluorobenzoyl isothiocyanate with hydrazines and their derivatives

Fluorinated derivatives of 4H-1,3-benzothiazin-4-one, [1,2,4]triazolo[4,3-a]pyrimidine, [1,2,4]triazolo[3,4-b][1,3]benzazoles, and 1,5-dihydro-1,2,4-triazole-5-thione were synthesized by addition of hydrazines and their derivatives to tetrafluorobenzoyl isothiocyanate, followed by cyclization of intermediate thiosemicarbazides.