Über 1.2.4.‐Triazole, VI. Die Kondensation methylsubstituierter Aminoguanidine mit aliphatischen Carbonsäuren

Kröger, Carl‐Friedrich; Schoknecht, Güter; Beyer, Hans

doi:10.1002/cber.19640970212

Cited by 17 publications

(6 citation statements)

References 10 publications

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“…Cyclic and acyclic pentaalkyl guanidines were obtained from 1,3-dimethyl-2-imidazolidinone, 1,3-dimethyl-3,4,5,6-tetrahydro-2(1 H )-pyrimidinone, tetrahydro-3,5-dimethyl-4 H -1,3,5-oxadiazin-4-one, and tetramethylurea by a published method (Scheme ) . 1,4-Dimethyl-5-methylimino-1,2,4-triazole, 13 , was prepared from N , N ‘, S -trimethylisothiourea hydroiodide and methyl hydrazine in ethyl alcohol which was then reacted with formic acid after the solvent had been removed . After the reaction was neutralized with NaOH solution, the pure product was obtained by using column chromatography.…”

Section: Resultsmentioning

confidence: 99%

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Guanidinium-Based Ionic Liquids

et al. 2005

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Cyclic (subset=N+<, subset = imidazolidine 3 and 4, hexahydro-pyrimidine 7 and 8, tetrahydro-1,3,5-oxadiazine 12, and triazoline 15 and 16) and acyclic [(R2N)2C=N+<, 19] guanidinium-based salts were synthesized via the quaternization of guanidine derivatives with nitric or perchloric acid or with iodomethane followed by metathesis reaction with silver nitrate, silver perchlorate, or ammonium dinitroamide. The structure of 15d was confirmed by single-crystal X-ray analysis. Most of the salts exhibited low melting points and good thermal stabilities. Their densities range between 1.2 and 1.5 g/cm3. Standard molar enthalpies of formation were calculated from experimentally determined constant-volume combustion energies obtained using an oxygen bomb calorimeter.

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Section: Resultsmentioning

confidence: 99%

“…However, for 16a and 16 b , there was no evidence of coupling based on the 1 H NMR spectra and H−H COSY measurements. Therefore, these are apparently ordinary acid salts …”

Section: Resultsmentioning

confidence: 99%

Guanidinium-Based Ionic Liquids

et al. 2005

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“…The method utilized by the Discovery Chemistry group to prepare aminotriazole 7 used a procedure reported by Kroger in 1964 which involved the nucleophilic displacement of methanethiol from S -methylisothiourea sulfate with methylhydrazine followed by treatment of the intermediate guanidine with formic acid . From the process perspective there were a number of concerns identified with this sequence which precluded it from further scale up, primarily the evolution of the highly toxic and flammable methanethiol byproduct together with the need for chromatographic purification.…”

Section: Resultsmentioning

confidence: 99%

Development of a Scaleable Process for the Synthesis of a Next-Generation Statin

Hobson

Akiti

Deshmukh

et al. 2010

Org. Process Res. Dev.

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This manuscript details the process research and development of a convergent and safe approach to 1 on a multikilo scale. Specific highlights of the process development efforts will be described, including the development of a dehydrogenation method for dihydropyrimidines and a thermochemically safe synthesis of a 1,2,4-aminotriazole fragment. A key feature of the synthesis is the use and optimization of a modified Julia-Kocienski olefination reaction. Specifically, we report an unprecedented dependence of the product olefin geometry on reaction temperature, where an E:Z ratio as high as 200:1 can be obtained. Initial insights into the mechanistic rationale for this observation are also provided. Finally, a purity upgrade sequence via an intermediate crystalline form is highlighted as a method of controlling the final API quality.

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“…As the temperature increased, the reaction mixture became homogeneous, but within 1 hr a precipitate formed. After 17 hr, the precipitate was collected by suction filtration and washed thoroughly with acetone to give 1-(2,4-dinitroanilino)biguanide hydrochloride (14) as orange crystals (2.2 g, 58%), mp 246-247°d ec. Re crystallization with DMF-95% EtOH afforded an analytical sample of fine orange needles, mp 250-251°dec.…”

Section: Methodsmentioning

confidence: 99%

Syntheses of C-amino- and C-azido-1,2,4-triazoles

Heitke¹,

Mccarty²

1974

J. Org. Chem.

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A series of C-amino-1,2,4-triazoles, substituted with methyl, dimethylamino, methoxy, and methylthio groups, was prepared from the appropriate JV-cyanoazomethines and either hydrazine or methylhydrazine (eq 1). C-Azido-1,2,4-triazoles were prepared from the corresponding amines by diazotization followed by reaction with azide ion. When these diazotization reactions were carried out, the C-amino-1,2,4-triazoles derived from methylhydrazine, unlike those derived from hydrazine, yielded varying quantities of products depending on the acidity of the reaction media. Ir and proton nmr spectra of the C-azido-1,2,4-triazoles in various solvents indicated that none of them participates in imidoyl azide-tetrazole tautomerism, even at -82°.

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Über 1.2.4.‐Triazole, VI. Die Kondensation methylsubstituierter Aminoguanidine mit aliphatischen Carbonsäuren

Cited by 17 publications

References 10 publications

Guanidinium-Based Ionic Liquids

Guanidinium-Based Ionic Liquids

Development of a Scaleable Process for the Synthesis of a Next-Generation Statin

Syntheses of C-amino- and C-azido-1,2,4-triazoles

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