Formaldehyde In Acetic Acid Research Articles

Dyeing Properties of Vilangin Synthesized from Embelin on Cotton Fibre

Semi synthesis involves the use of chemical compounds isolated from natural sources as the starting materials to produce other distinct compounds with added value and improved chemical properties. Most modified dyes have been synthesized through chemical modification to increase solubility and fastness properties of the dyes. A semi-synthetic dye (vilangin) has been obtained through chemical modification of embelin (a benzoquinone) isolated from Embelia schimperi berries crude extract, a plant-based dye. The vilangin dye was synthesized by condensation of embelin with formaldehyde in acetic acid solution., Their melting point and thin layer chromatography was done to determine purity. Characterization was done using Ultraviolet–Visible spectroscopy, Fourier Transform Infrared spectroscopy, Liquid chromatography Mass spectrometry and Nuclear Magnetic Resonance Spectroscopy. Embelin and the semi- synthesized dye were applied on cotton fabrics and colour fastness properties such as wash fastness, rubbing fastness, light fastness were evaluated. Embelin dye and vilangin dye exhibited similar colour strengths (K/S values) of 0.18 and 0.19 respectively. Use of mordants increased the colour strengths from 0.19 to 0.23 for the pre-mordanted cotton fibers ,the post-mordanted were in the range of 0.19-0.32 whereas the simultaneous mordanting showed better characteristics in the range of 0.27-0.52 for the vilangin dye. It has thus been established that the semi-synthetic dye possessed superior fastness properties compared to the parent embelin dye.

Redox Reactions in Chromium-Containing Fixatives for Biological Materials

Abstract—A study of redox reaction kinetics in chromium-containing fixatives (mixtures of chromic acid, bichromate, formaldehyde, and acetic acid) showed that these fixatives were unstable chemical mixtures characterized by rapid kinetics of redox processes. Therefore, biological material fixation occurs in a non-stationary solution of a variable composition, including chromic acid, bichromates (chromium(VI)), formaldehyde, acetic acid, formic acid, and chromium(III) acetate. We propose the division of chemical fixation in these fixatives into two successive stages (“two-step fixation protocol”): the tissue is fixed in an acetic acid–formaldehyde mixture (a rapidly penetrating fixing mixture) at the first stage and washed thoroughly, and treated by the mordant for the staining at the second stage. Such a protocol will at least preserve the original composition of chromium-containing fixatives.

Novel Mannich-type nucleophilic substitution reaction with tertiary aromatic amines

A novel formaldehyde-mediated condensation reaction of N,N-dialkyl aromatic amines and resonance-stabilized carbon nucleophiles is described. A condensation reaction between N,N-dimethylaniline ( 4 ) and ethyl acetoacetate ( 8 ) in the presence of formaldehyde in acetic acid took place to give 2-(4-dimethylaminobenzyl)-3-oxo butyric acid ethyl ester ( 9 ) together with the dimerization product 7 in 73 and 21% yields, respectively. This condensation reaction was further applied to the synthesis of 4-substituted dialkylaniline derivatives.

１‐アズレンメタノールのα，３‐分子間脱水オリゴマーの合成

Treatment of azulene (1) with 0.2% formaldehyde in acetic acid under nitrogen at 25°C for 1 h gave five products: Namely, 1, 1'-methylenebisazulene (2), 1, 3-bis (1-azulenylmethyl) azulene (3), 1, 1'-methylenebis [3- (1-azulenylmethyl) azulene] (4), 1, 3-bis [3- (1-azulenylmethyl) -1-azulenylmethyl]azulene (5), and 1, r-methylenebis[ [3- (1-azulenylmethyl)-1-azulenylmethyl]azulene] (6). The structures of the products were established on the basis of their spectroscopic (UV-vis., MS, and 1H-NMR) data.

Preparations of Optically Active Homocysteine and Homocystine by Asymmetric Transformation of (RS)-1,3-Thiazane-4-carboxylic Acid

Abstract Dl-Homocysteine [Dl-Hcy] from (RS)-homocysteine thiolactone hydrochloride [(RS)-HTL·HCl] was subjected to reaction with formaldehyde in acetic acid to give (RS)-1,3-thiazane-4-carboxylic acid monohydrate [(RS)-THA·H2O]. An asymmetric transformation of (RS)-THA·H2O was achieved via salt formation with optically active tartaric acid in the presence of salicylaldehyde in acetic acid. The (R)- and (S)-THA obtained, respectively, from the salt of (R)-THA with (2R, 3R)-tartaric acid and its enantiomeric salt were treated with hydroxylamine hydrochloride to give d- and l-Hcy of 100% optical purity, respectively, in 50% yield from (RS)-HTL·HCl. Oxidation of d- and l-Hcy with hydrogen peroxide gave d- and l-homocystine, respectively, in 47% yield.

The Interpretation of an Abnormal Reaction Path Occurring during the Methylation of Certain Secondary Norbornanemethylamines with Formaldehyde in Acetic Acid.

The Interpretation of an Abnormal Reaction Path Occurring during the Methylation of Certain Secondary Norbornanemethylamines with Formaldehyde in Acetic Acid.

ChemInform Abstract: THE PRINS REACTION OF CYCLOOCTENE AND CYCLODODECENE

Chemischer InformationsdienstVolume 4, Issue 44 Preparative Organic Chemistry ChemInform Abstract: THE PRINS REACTION OF CYCLOOCTENE AND CYCLODODECENE AKIRA UCHIDA, AKIRA UCHIDASearch for more papers by this authorTOYOHIRO MAEDA, TOYOHIRO MAEDASearch for more papers by this authorSUMIO MATSUDA, SUMIO MATSUDASearch for more papers by this author AKIRA UCHIDA, AKIRA UCHIDASearch for more papers by this authorTOYOHIRO MAEDA, TOYOHIRO MAEDASearch for more papers by this authorSUMIO MATSUDA, SUMIO MATSUDASearch for more papers by this author First published: October 30, 1973 https://doi.org/10.1002/chin.197344152Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume4, Issue44October 30, 1973 RelatedInformation

Synthesis of high temperature resistant anisolic resins

AbstractSimple and substituted anisoles have been condensed with formaldehyde in acetic acid under different conditions of catalyst concentration and reaction temperatures. The anisolic resins thus obtained have been characterized by infrared and ultraviolet spectra. They are found to be linear molecules having mainly methylene bridges between the structural units.

The Prins Reaction of Cyclooctene and Cyclododecene

Abstract The reaction products of the sulfuric acid-catalyzed condensation of cyclooctene or cyclododecene with formaldehyde in acetic acid at 40 °C were investigated. The reaction of cyclooctene gave a mixture of 4,5-hexa-methylene-1,3-dioxane, 2-cyclooctenylmethyl acetate, and 1-acetoxy-2-acetoxymethylcyclooctane, while reaction of cyclododecene gave a mixture of cyclic ethers; one was identified as 3-oxabicyclo[10,3,0]-6-pentadecene, and the others were estimated to be 15-acetoxy-3-oxabicyclo[9,3,1]pentadecane and 12,17-dioxatricyclo[13,3, 0,010,14]-2-octadecene.

Etats du formaldehyde dans l'acide acetique en presence d'acide sulfurique

A quantitative analysis of solutions of formaldehyde in acetic acid has been performed for various concentrations of formaldehyde, sulfuric acid and water, by proton magnetic resonance spectroscopy. In such solutions formaldehyde exists as trioxane and diacetates of methyleneglycol and polyoxymethyleneglycols. These forms of formaldehyde are in equilibria which are discussed.

The reaction of 3-propylindole with aldehydes preparation of 2-(α-aminoalkyl) indoles

Abstract 2,2′-Benzylidenebisindoles ( 5 ) are produced by the condensation of 3-propylindole with aromatic aldehydes. It is shown that aromatic aldehydes react initially, but reversibly, at nitrogen. N-substituted products can be trapped as acetate derivatives ( 7 ) and are converted to 2,2′-benzylidenebisindoles ( 5 ) under the original reaction conditions. 3-Propylindole reacts with formaldehyde and piperidine under mild conditions to give 1-piperidinomethyl-3-propylindole. 2-Piperidinomethyl-3-propylindole is obtained when the reaction with formaldehyde in acetic acid is carried out at 100° in the presence of excess piperidine. The condensation of 3-propylindole with formaldehyde and primary amines involves initial attack at nitrogen followed by intramolecular substitution at the 2-position to yield 1H-imidazo[1,5 a ]indole and 2,3,4,5-tetrahydrotriazepino[1,7 a ]indole derivatives. Hydrolysis of cyclohexylimidazoindole ( 11 ) affords 2-cyclohcxylaminomethyl-3-propylindole.

Condensation of Octene-2 with Formaldehyde

In the previous report, authors studied the acid catalyzed condensation of octadecene-1 with formaldehyde in acetic acid, and the products were 4-hexadecyl-1, 3-dioxane, 3-pentadecyl-4-hydroxytetrahydropyrane and nonadecadiol-1, 3, respectively.In this paper, authors investigated the simillar reaction of octene-2 with formaldehyde.The reaction products were saponified and fractionated mainly by chromathography and following substances were separated.The characteristics of these substances were identified to those of 4-methyl-5-pentyl-1, 3-dioxane, 3-penthyl-4-hydroxytetrahydropyrane and 2-pentyl-3-hydroxybutanol-1, respectively.

Condensation of Octadecene-1 with Formaldehyde

Authors investigated the condensation of octadecene-1 with formaldehyde in acetic acid at the presence of perchloric acid as, the catalyst.The reaction products were saponified and fractionated by recrystallization and chromatography, and three substances were separated. The characteristics of these substances were corresponded to those of nonadecadiol-1, 3 (mp 75-75.5°C), 3-pentadecatetrahydropyranol-4 (mp 65-66°C) and octadecanol (mp 41-44°C., mixture of alkanol-2 and-3), respectively.The presence of alkyl-1, 3-dioxan, known as one of the main products of lower olefine condensed with formaldehyde, was also recognized in this case from IR spectrum of the lower melting fractions of the filtrate, but it was not isolated because of its small quantity.As the catalyzer, perchloric acid was more effective than followed sulfuric acid and borontrifluoride etherate in the above reactions. The larger the quantity of paraformaldehyde used against olefine, the greater the yield of the products obtained, but more pyranol was obtained in case of 1 : 1 molar ratio than other cases (Table 1).The saponification value of the product was the highest at 3 hr reaction time, and the reaction was seemed to proceed easily (Fig. 4).Octadecene-1 did not react with formaldehyde without acetic acid in inert solvent such as ethanol or in the presence of 50% acetic acid, also it did not react with aqueous formalin even in acetic acid (Table 3).

Telomerization and prins reaction of styrene and formaldehyde in acetic acid. The role of cyclic formal in the reaction mechanism

AbstractThe effect of variations in the reaction conditions on the composition of the end product was studied in the reaction of styrene with formaldehyde in acetic acid. Initially a relatively large amount of 4‐phenyl‐1,3‐dioxan is formed along with telomer homologues. This cyclic formal is cleaved by protolysis in a comparatively slow secondary reaction with styrene; it thus acts as an intermediate formaldehyde donor.The results are interpreted in terms of a carbonium‐ion mechanism.

Phenol‐formaldehyde and allied resins. V.—Synthesis of a bridged decanuclear novolak and a case of hardening by way of meta‐substitution

AbstractThe bridged decanuclear novolak (V) has been synthesized rationally as a non‐crystalline chemical individual from 2: 6‐bis‐2′‐hydroxy‐5′‐methylbenzyl‐4‐bromophenol (I) by way of the dimethylol derivative (II) which on reaction with 2: 4‐xylenol furnished 2: 6‐bis‐2′‐hydroxy‐3′‐(2″‐hydroxy‐3″: 5″‐dimethylbenzyl)‐5′‐methylbenzyl‐4‐bromophenol (III) which was debrominated to the pentanuclear novolak (IV). On reaction with an equivalent of formaldehyde in acetic acid, using sulphuric acid as catalyst, the latter gave the required bridged decanuclear novolak (V). In the presence of excess of acid formaldehyde, both the pentanuclear and the decanuclear novolaks were readily converted into hardened products whose infra‐red absorption spectra indicated the formation of methylene bridges in meta‐position to the hydroxyl groups.