Hexamethylenetetramine aldehydes

Hexamethylenetetramine Aldehydes from halides Sommelet reaction... 

From ehloromethyl or bromomethyl aromatic compounds by heating with hexamethylenetetramine (hexamine) in aqueous alcohol or aqueous acetic acid. A quaternary ammonium compound is formed, which yields the aldehyde upon treatment with water in the presence of hexamine for example... 

In a 500 ml. flask, fitted with a reflux condenser, place 53 g. of 1-chloro-methylnaphthalene (Section IV.23), 84 g, of hexamethylenetetramine and 250 ml. of 1 1 acetic acid [CAUTION 1-Chloromethylnaphtha-lene and, to a lesser degree, a-naphthaldehyde have lachrymatory and vesicant properties adequate precautions should therefore be taken to avoid contact with these substances.] Heat the mixture under reflux for 2 hours it becomes homogeneous after about 15 minutes and then an oil commences to separate. Add 100 ml. of concentrated hydrochloric acid and reflux for a further 15 minutes this will hydrolyse any SchifiF s bases which may be formed from amine and aldehyde present and will also convert any amines into the ether-insoluble hydrochlorides. Cool, and extract the mixture with 150 ml. of ether. Wash the ether layer with three 50 ml. portions of water, then cautiously with 50 ml. of 10 per cent, sodium carbonate solution, followed by 50 ml. of water. Dry the ethereal solution with anhydrous magnesium sulphate, remove the ether by distillation on a steam bath, and distil the residue under reduced pressure. Collect the a-naphthaldehyde at 160-162718 mm. the yield is 38 g. 

Unlike aliphatic aldehydes (with the exception of formaldehyde which 3delds hexamethylenetetramine. Section 111,67) benzaldehyde yields hydrobenzamide (and not an aldehyde ammonia) with ammonia ... 

Sommelet process org chem The preparation of thiophene aldehydes by treatment of thiophene with hexamethylenetetramine.. so-mal ya, pra-s3s ) Sonnenschein s reagent analychem A solution of phosphomolybdicadd that forms a yellow precipitate with alkaloid sulfates. z6n-3n,shTnz r5,a-j3nt) sonocatalysis chem 1. Initiation of a catalytic reaction by irradiation with sound or ultrasound. 2. Use of sound to impart catalytic activity to a chemical compound. san-3-k3 tal-3-s3s)... 

Another way to oxidize primary alkyl halides to aldehydes is by the use of hexamethylenetetramine followed by water. However, this reaction, called the Sommelet reaction. is limited to benzylic halides. The reaction is seldom useful when the R in RCH2CI is alkyl. The first part of the reaction is conversion to the amine ArCH2NH2 (0-44), which can be isolated. Reaction of the amine with excess hexamethylenetetramine gives the aldehyde. It is this last step that is the actual Sommelet reaction, though the entire process can be conducted without isolation of intermediates. Once the amine is formed, it is converted to an imine (ArCH2N=CH2) with formaldehyde liberated from the reagent. The key step then follows transfer of hydrogen from another mole of the arylamine to the imine ... 

This last imine is then hydrolyzed by water to the aldehyde. Alternatively, the benzylamine may transfer hydrogen directly to hexamethylenetetramine. 

Amine Peroxides as Explosives. Some amines may yield expl peroxides. For instance, hexamethylenetetramine when treated with hydrogen peroxide in the presence of an organic add(citric) which combines with the liberated Nris, forms hexamethylenetriperoxidediamineiqv) (Ref IX Schif f s bases, ammoniacal aldehydes or their... 

SOMMELET REACTION. Preparation of aldehydes from aralkyl or alkyl halides by reaction with hexamethylenetetramine followed by mild hydrolysis of the formed quaternary salt,... 

The oxidation of a-hydroxy acids by benzyltrimethylammonium tribromide (BTMAB) to the corresponding carbonyl compounds shows a substantial solvent isotope effect, A (H20)/A (D20) = 3.57, but no KIE for a-deuteromandelic acid.133 The oxidation of glucose by hypobromous acid is first order in glucose and the acid.134 [l,l-2H2]Ethanol shows a substantial kinetic isotope effect when oxidized by hexamethylenetetramine-bromine (HABR) in acetic acid to aldehyde.135 Kinetics of the oxidation of aliphatic aldehydes by hexamethylenetetramine-bromine have been studied by the same group.136 Dioxoane dibromide oxidizes y-tocopherol to 5-bromomethyl-y-tocopherylquinone, which spontaneously cyclizes to 5-formyl-y-tocopherol.137... 

Aromatic and heteroaromatic aldehydes can alternatively be prepared from the corresponding methyl compound by subjecting the chloromethyl or bromomethyl derivative to the Sommelet reaction. This procedure involves an initial reaction between the halomethyl compound and hexamethylenetetramine (hexamine), and hydrolysing the resulting quaternary hexamine salt (4) with hot aqueous acetic acid. 

The condensation products of aldehydes with ammonia or amido-eoinpounds are easily reduced to amines in sulphuric-acid solution at lead cathodes. Thus hexamethylenetetramine yields methylamine (Knudson 2) ethylideneimine, ethylamine the base from acetaldehyde and ethylamine, diethylamine. Aromatic aldehydes behave similarly. The Farbwerke vorm. Meister,... 

Acid Amides can be produced by acylating ammonia with esters, acid anhydrides, or the acids themselves (above 100 °C) an important product is formamide from methyl formate. Alternatively acid amides can be synthesized by reacting acid halides with ammonia. Catalytic hydrogenation converts the acid amides to primary amines. Ammonia and aldehydes or ketones are the basis for different stable products. With formaldehyde hexamethylenetetramine (urotropine) is obtained with acetaldehyde, ammono acetaldehyde with benzaldehyde, hydrobenzamide with ethylene and propylene oxides, aqueous ammonia reacts to form ethanol- or propanolamine. 

Duff reaction (1, 430). Review. In the clastical procedure highly activated aromatic compounds are converted into their formyl derivatives by treatment with hexamethylenetetramine and glyceroboric acid yields are generally low. Smith finds that a variety of aromatic compounds, including simple hydrocarbons, when treated with hexamethylenetetramine in conjunction with trifluoroacetic acid al reflux temperature (82- 90") arc converted into i mine products which yield aldehydes on hydrolysis ... 

Hexamine (hexamethylenetetramine or methenamine), C5H12N4 (white crystals, mp 280 C, sublimes), reacts with reactive (allylic or ben-zylic) halides to form salts, which, on steam distillation or refluxing with water, yield aldehydes [955, 956] [Sommeletreaction). Aromatic aldehydes can be obtained from benzyl chlorides on treatment with formaldehyde and hydrochloric acid and subsequent refluxing with hexamethylenetetramine [957],... 

A solution of 14 kilos of hexamethylenetetramine in 40 litres of alcohol of 60 per cent, strength is mixed with 12.5 kilos of benzyl chloride and the mixture is heated on then water bath in a reflux apparatus for 5-6 hours 20 litres of water are then added, the greater part of the alcohol distilled away and the residue carried over with steam. The liquid carried over is extracted by means of a volatile solvent and the aldehyde is purified by means of its bisulphite compound. The yield of purified benzaldehyde amounts to 7.5 to 9 kilos. 

The reaction may also be carried out without addition of alcohol, that is to say in an aqueous solution. Thus, 12.65 kilos of benzyl chloride are heated for two hours with a solution of 14 kilos of hexamethylenetetramine in 60 litres of water, and the aldehyde is then distilled with steam after purification with sodium bisulphite a good yield of benzaldehyde is obtained. Source Fabriques 1914... 

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