Showing papers on "Hydrazone published in 1972"

Prediction of Colour Change in Dye Equilibria I-Azo and Hydrazone Tautomers and Anions of 4-Phenylazo-1-naphthols

Abstract: When a dye can exist in two forms in equilibrium, the difference in frequency between their visible absorption bands should exhibit a linear relation with Hammett substituent constants. This has been tested successfully with the 4-phenylazo-1-naphthols for the frequency shifts between their azo and hydrazone tautomeric forms and their common anions in alkali. The practical and theoretical significance of these results is discussed.

Triazines and related products. Part X. A re-examination of the reaction between benzil and diaminoguanidine nitrate

Abstract: Benzil reacts with diaminoguanidine nitrate to yield the nitrate salt of benzil mono[(aminoamidino)hydrazone](2). The hydrazone (2) is unstable, and cyclises on melting or in solvents to 5,6-diphenyl-3-hydrazino-1,2,4-triazine (3). Diazotisation of the hydrazone (2) and of hydrazine (3) affords the same product, 6,7-diphenyltetrazolo-[1,5-b]-as-triazine (9) which decomposes in boiling secondary amines to yield substituted 3-amino-5,6-diphenyl-1,2,4-triazines and hydrazoic acid. Both the hydrazone (2) and the hydrazine (3) react with triethyl orthoformate or formic acid to give 6,7-diphenyltriazolo[4,3-b]-as-triazine (16), which was also prepared, unambiguously, from benzil and 3,4-diamino-1,2,4-triazole. Although conditions favourable for Dimroth rearrangement were employed, no such transformations were encountered in the reactions of the bicyclic systems (9) and (16).

The reactions of substituted benzothiazol-2-ylhydrazones with bromine: a route to s-triazolo[3,4-b][1,3]benzothiazoles

Abstract: The products of the reaction of p-substituted benzaldehyde benzothiazol-2-ylhydrazones with bromine depended on the molar ratio of the reactants and the reaction time. With 1 mol of bromine and short reaction times hydrazone bromonium bromides and perbromides were formed. With 0·5 mol of bromine and longer reaction times the products included hydrobromides, hydrazonyl bromides, and 6 -bromobenzothiazol-2-ylhydrazones. Cyclisations of the hydrazonyl bromides were investigated and as well a single-step cyclisation of the parent hydrazones with bromine was developed as an efficient cyclisation route to s-triazolo[3,4-b][1,3]benzothiazoles.

Reactions of bromine and lead tetra-acetate with 2-(substituted hydrazino)-5-phenyl-1,3,4-oxadiazoles: routes to 3-aryl-6-phenyl-1,2,4-triazolo[3,4-b][1,3,4]oxadiazoles

Abstract: 2-(Substituted hydrazino)-5-phenyl-1,3,4-oxadiazoles react with bromine in acetic acid to yield hydrazone perbromides, or hydrazonyl bromides in the presence of sodium acetate. Treatment of the hydrazonyl bromides with triethylamine in benzene or solvolysis in aqueous solvents results in cyclisation to the new 1,2,4-triazolo[3,4-b]-[1,3,4]oxadiazole ring system. The cyclisation involves the oxadiazole ring as a nucleophile which attacks the labile carbon–bromine site in the hydrazonyl bromide. In the solvolysis, this internal nucleophilic attack is in competition with external nucleophilic attack by solvent molecules, and direct solvolysis products are also obtained. A second route to the new ring system with tribromodiazabutadienes has also been developed. The oxadiazole ring of the new 1,2,4-triazolo[3,4-b][1,3,4]oxadiazoles is labile to acid and base and a preferential ring interconversion pattern of oxadiazole to triazole has been noted. In the reaction of the 2-(substituted hydrazino)-5-phenyl-1,3,4-oxadiazoles with lead tetra-acetate, the presence of the oxygen atom at the potential cyclisation site inhibits the cyclisation. The'reaction instead involves acetoxylation of the hydrazone and only gives, at most, traces of 1,2,4-triazolo[3,4-b][1,3,4]oxadiazoles.

Anti-arthropodal formulation and method

Abstract: Certain new benzoyl chloride (fluoroalkylphenyl)-hydrazones have been found to be active against arthropod pests and worms. The characterizing fluoroalkyl group on the phenylhydrazone ring can be associated with other substituent atoms and groups. The benzoyl ring can also be substituted. Representative substituent atoms and groups include the halogen atoms, lower-alkyl groups, lower-alkoxy groups, and a nitro group. The fluoroalkyl group is more meaningfully designated an '''' Alpha -Fnalkyl'''' group because fluorine atom substitution on the Alpha -carbon appears to be advantageous. The new compounds can be prepared by reacting a benzoic acid 2( Alpha -Fnalkylphenyl)hydrazide with phosphorus pentachloride to obtain a benzoyl chloride ((dichlorophosphinyl- Alpha Fnalkyl)phenyl)hydrazone that is reacted with phenol to produce the desired benzoyl chloride ( Alpha -Fnalkylphenyl)hydrazones. The compounds having chlorine on the phenylhydrazone ring can be prepared by direct halogenation of benzaldehyde ( Alpha Fnalkylphenyl)hydrazones or a benzoyl chloride ( Alpha Fnalkylphenyl)hydrazone. Methods of anti-arthropodal use and novel formulations adapted for biological use of the new compounds are also described.

Incorporation of 3-Methyl-2-benzothiazolone Hydrazone into the Anticodon Loop of tRNAPhe from Yeast

Abstract: The incorporation of 3-methyl-2-benzothiazolone hydrazone into the anticodon loop of tRNAPhe from yeast after excision of the base Y has been studied with respect to concentration, pH and temperature. Model reactions were performed at the monomer level with ribose and ribose 5-phosphate and at the oligomer level with a tRNAPhe anticodon-arm dodecanucleotide from which the base Y had been excised. The reaction is easily followed by ultraviolet spectroscopy. The reaction product exhibits weak fluorescence. The covalent attachment of 3-methyl-2-benzothiazolone hydrazone to the nucleotide chain is stable. As shown by nucleoside analysis no side reactions occur and the incorporation of 3-methyl-2-benzothiazolone hydrazone into tRNA is quantitative. After modification tRNAPhe is fully chargeable.

Heterocyclic imines and amines. Part XIV. Products from 2,5-di-iminopyrrolidine (succinimidine) and hydrazine

Abstract: Hydrazine (in excess) reacts with 2,5-di-iminopyrrolidine (1) or succinonitrile to yield 6-hydrazino-3-hydrazono-2,3,4,5-tetrahydropyridazine (2). Treatment of this with acetone, glyoxylic acid, and butyl glyoxylate affords the expected di-condensation products; with glyoxal a polymeric hydrazone is obtained. Acylation of compound (2) with ethyl chloroformate was successful but attempts to oxidise the product to known pyridazines failed, as did attempts to dehydrogenate compound (2) to 3,6-dihydrazinopyridazine. 5-lmino-2-pyrrolidone (13) with hydrazine gave 6-hydrazino-4.5-dihydropyridazin-3(2H)-one (14).In hot pyridine, succinonitrile reacts with an equimolar quantity of hydrazine to give a polymer, (C4H6N4)n; with 2 molecular proportions a dimeric condensation product, C8H16N10, results. Structures for these are proposed on the basis of spectral and other evidence. The behaviour of these compounds and related pyridazines on thermolysis is reported.

The charge-transfer complex and photochemical reaction of 9-anthraldehyde hydrazone in sulphur dioxide–oxygen

Abstract: The 1 : 1 charge-transfer complex of 9-anthraldehyde hydrazone with sulphur dioxide is not ionic in the ground state. Photolysis of the hydrazone in liquid sulphur dioxide or in liquid sulphur dioxide–carbon tetrachloride yielded 9-anthraldehyde azine (I) and nitrogen via N–N scission only. The quantum yield for formation of compound (I) varied with solvent and the concentrations of sulphur dioxide and oxygen. Quenching experiments indicated the intermediacy of a triplet charge-transfer complex between the hydrazone and sulphur dioxide. The rate constant for quenching of the complex, kaca. 3·0 × 108 l mol–1s–1, and the equilibrium constant for formation of the complex, K3ca. 1·7 × 102 l mol–1, were evaluated from experiments in the presence of air. Addition of oxygen caused a large increase in the quantum yield for formation of compound (I), suggesting that it is formed from an ionic intermediate via the triplet charge-transfer complex.

Electrophilic substitution in a basic hydrazone system: the first synthesis of N-pyridylhydrazonyl bromides

Abstract: A kinetic study of the bromination of substituted benzaldehyde 3-pyridylhydrazones in 70% acetic acid has shown that the protonated hydrazone species is brominated. In water, both protonated and free hydrazones (the latter 162-fold more rapidly) react with bromine. The products formed are the corresponding N-(3-pyridyl) substituted benzohydrazonyl bromides, rather than N-bromo-complexes, and substituent effects (ρ=–0·42 for C-aryl ring and –1·42 for N-pyridyl ring) are in accord with direct electrophilic attack at methine carbon atom. The novel hydrazonyl bromides (isolated as hydrobromides) may be readily hydrolysed to N-(3-pyridyl) substituted benzohydrazides and react with azide ion to give benzohydrazonyl azides.

Esterification of penicillin acids

Abstract: THE INVENTION PROVIDES A METHOD OF ESTERIFYING N-BLOCKED AMINO ACIS BY REACTION OF THE N-BLOCKED ACID WITH A HYDRAZONE AND AN OXIDISISNG AGENT.

Process for the preparation of certain indolobenzazepine derivatives

Abstract: A TWO-STEP PROCESS FOR THE PREPARATION OF 1,2,3,4,8,9HEXAHYDRO-(3-SUBSTITUTED)PYRIDO)4'',3'':2,3)INDOLO(1,7-AB) (1)BENZAZEPINES, USEFUL AS TRANQUILIZERS AND/OR ANALGESICS IN WARM:BLOODED ANIMALS, OR AS INTERMEDIATES IN THE PREPARATION OF THESE, INVOLVES REACTION OF N-NITROSOIMINODIBENZYL WITH 4-PIPERIDONE OR AN N-SUBSTITUTED DERVATIVE OF 4-PIPERIDONE IN THE PRESENCE OF ZINC AND ACETIC ACID, AND CYCLIZATION OF THE RESULTING HYDRAZONE WITH STRONG ACID.

Benzo[c]fluorenones. IV. The Elucidation of the Position of the Succinoyl Group introduced in 2,7-Diethylfluorene and the conversion of this compound into 1,2,3,4-tetrahydro-5,9-diethylbenzo[c]fluorene

Abstract: 2,7-Diacetylfluorene was reduced to 2,7-diethylfluorene. Succinoylation of this latter compound gave γ-keto-γ-[4-(2, 7-dietyl)-fluorenyl] butyric acid. The position of attack of the succinoyl group was definitely proved to be in position 4. A pyridazinone has been obtained in a trial to obtain a hydrazone derivative. The infrared spectrum has been used to elucidate the end of a reduction reaction.

5-substituted benzophenone hydrazone compounds and process for the production thereof

Abstract: 5-SUBSTITUTED BENZOPHENONE HYDRAZONES WHICH POSSESS AN ACTIVITY ON THE CENTRAL NERVOUS SYSTEM ARE DISCLOSED. THE 5-SUBSTITUTED BENZOPHENONE HYDRAZONES ARE PREPARED BY THE REACTION OF 5-SUBSTITUTED BENZOPHENONES WITH HYDRAZINE.

Synthesis of pyrazolines by the condensation of monoalkyl hydrazones with aldehydes

Abstract: Acetaldehyde readily condenses with its monalkyl hydrazones with the formation of 1-alkyl-5-methyl-2-pyrazolines. A number of pure 2pyrazolines have been synthesized in this way with yields of 40–60%. In the condensation of propionaldehyde with its isopropyl hydrazone, because of the occurrence of rearrangements and the nonstereospecificity of the process, a mixture of structural and stereoisomeric 2-pyrazolines is formed. The promising condensation of aldehydes with monalkyl hydrazones of other aldehydes and ketones is accompanied by “transhydrazonation,” which limits the preparative possibilities of this reaction.

The Synthesis and Diazotization of Some Ketone Hydrazones

Abstract: Hydrazones have been synthesized in this study both from a variety of bicyclic ketones and from ketones containing either the 1-naphthyl or 2-naphthyl group. Three of these hydrazones, those derived from 1-acetonaphthone, 2-acetonaphthone, and benzosuberone, have not been reported previously in the literature. All of the hydrazones were allowed to rearrange in a diazotizing medium to produce amide products. One of these, 4,5-benzoai-heptanolactarn, has never been reported in the literature. From the results of this research, it is possible to reaffirm some general conclusions concerning the utility and scope of the hydrazone diazotization-rearrangement. Among these are the facts that the reaction generally functions well only if at least one aromatic ring is present and that it is stereospecific with migration of the group anti to the NH2 group of the original hydrazone. Thus, the assignment of hydrazone isomer configuration appears to be possible on the basis of the identity of the given amide product. Such assignments have been made for the compounds studied here. Some postulations concerning the steric requirements for hydrazone formation with the aromatic bicyclic ketones have also been made. INTRODUCTION The rearrangement of ketone hydrazones in a diazotizing medium to produce amides was first reported by Pearson and Greer (1949). Equation 1 illustrates this reaction with benzophenone hydrazone (1) which gives benzanilide (5) as the final product. (In this paper, the underlined number, _1, refers to the structural formula which has beneath it that same underlined number. This type of referral follows throughout the paper for structures 2 through 26. The names of less common compounds are also included beneath the structure.) 1,2-shifty f ^ A f ' i i = = c — l r \ l aqueous x Equat ion 1 aqueous base Further studies were made by Carter (1952) and by Pearson, Carter, and Greer (1953). These experiments revealed that the diazotization-rearrangement was generally applicable to ketone hydrazones. They postulated that the mechiManuscript received June 29, 1971. THE OHIO JOURNAL OF SCIENCE 72(5): 276, September 1972. No. 5 DIAZOTIZATION OF KETONE HYDRAZONES 277 anism of the process was probably similar to that of the Beckmann rearrangement of ketone oximes. When an unsymmetrical ketone, such as 4-bromobenzophene (6), was employed in reaction with aqueous hydrazine (Equation 2), the two geometric isomers 7 and 8 were isolated. When each of these was rearranged in a separate diazotizing reaction medium, isomeric benzanilide products (9 and 1,0) resulted, as illustrated by Equations 3 and 4. Pearson, Carter, and Greer (1953)