Hydrofuramide is a

condensation Condensation is the change of the state of matter from the gas phase into the liquid phase, and is the reverse of vaporization. The word most often refers to the water cycle. It can also be defined as the change in the state of water vapor to ...

product of three molar equivalents of

furfural Furfural is an organic compound with the formula C4H3OCHO. It is a colorless liquid, although commercial samples are often brown. It has an aldehyde group attached to the 2-position of furan. It is a product of the dehydration of sugars, as occurs ...

with two molar equivalents of

ammonia Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous was ...

. Hydrofuramide is a crystalline solid with a melting point of 118-119 °C. The molecule may be described as a

diimine Diimines are organic compounds containing two imine (RCH=NR') groups. Common derivatives are 1,2-diketones and 1,3-diimines. These compounds are used as ligands and as precursors to heterocycles. Diimines are prepared by condensation reactions ...

with three pendant furanyl rings. Hydrofuramide is a versatile specialty chemical with applications in diverse areas, including

rubber Rubber, also called India rubber, latex, Amazonian rubber, ''caucho'', or ''caoutchouc'', as initially produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds. Thailand, Malaysia, and ...

additives, pharmaceutical intermediates,

preservatives A preservative is a substance or a chemical that is added to products such as food products, beverages, pharmaceutical drugs, paints, biological samples, cosmetics, wood, and many other products to prevent decomposition by microbial growth or by ...

, and

rodenticides Rodenticides are chemicals made and sold for the purpose of killing rodents. While commonly referred to as "rat poison", rodenticides are also used to kill mice, squirrels, woodchucks, chipmunks, porcupines, nutria, beavers, and voles. Despite ...

Synthesis

Hydrofuramide was prepared in 1960 by Kapur via the reaction of furfural with aqueous ammonia in chilled

ethanol Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an Alcohol (chemistry), alcohol with the chemical formula . Its formula can be also written as or (an ethyl ...

solution.

Reactions

The reactive

imine In organic chemistry, an imine ( or ) is a functional group or organic compound containing a carbon–nitrogen double bond (). The nitrogen atom can be attached to a hydrogen or an organic group (R). The carbon atom has two additional single bo ...

double bonds of hydrofuramide are easily reduced. Reduction with aqueous

sodium borohydride Sodium borohydride, also known as sodium tetrahydridoborate and sodium tetrahydroborate, is an inorganic compound with the formula Na BH4. This white solid, usually encountered as an aqueous basic solution, is a reducing agent that finds appli ...

yields ''N'',''N''-bisfurfuryl-2-furylmethanediamine, useful as an antihypertensive drug compound.

Catalytic Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...

hydrogenation Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a Catalysis, catalyst such as nickel, palladium or platinum. The process is commonly employed to redox, reduce or S ...

of hydrofuramide with Raney nickel in the presence of ammonia in ethanol yields mixtures of

furfurylamine Furfurylamine is an aromatic amine typically formed by the reductive amination of furfural with ammonia. The pharmaceutical drug furtrethonium, a parasympathomimetic cholinergic, is a trimethyl ammonium derivative (chemistry), derivative of furfu ...

and difurfurylamine. By contrast, hydrogenation in

acetic acid Acetic acid , systematically named ethanoic acid , is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main component ...

-ethanol, employing

platinum oxide Adams' catalyst, also known as platinum dioxide, is usually represented as platinum(IV) oxide hydrate, PtO2•H2O. It is a catalyst for hydrogenation and hydrogenolysis in organic synthesis. This dark brown powder is commercially available. The ox ...

catalyst yielded the

tertiary amine In chemistry, amines (, ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (), wherein one or more hydrogen atoms have been replaced by a substituent such a ...

tri-furfurylamine after neutralization. Furthermore,

lithium aluminium hydride Lithium aluminium hydride, commonly abbreviated to LAH, is an inorganic compound with the chemical formula Li Al H4. It is a white solid, discovered by Finholt, Bond and Schlesinger in 1947. This compound is used as a reducing agent in organic ...

reduction of hydrofuramide yields furfurin, a tetracyclic compound.

Applications

Rubber vulcanization

Hydrofuramide has shown effectiveness as a synergist with

zinc stearate Zinc stearate is a "zinc soap" that is widely used industrially. In this context, soap is used in its formal sense, a metal salt of a fatty acid: in this case stearic acid. It is a white solid that repels water. It is insoluble in polar solvents s ...

in enhancing the rate of

vulcanization Vulcanization (British: Vulcanisation) is a range of processes for hardening rubbers. The term originally referred exclusively to the treatment of natural rubber with sulfur, which remains the most common practice. It has also grown to include ...

styrene-butadiene rubber Styrene-butadiene or styrene-butadiene rubber (SBR) describe families of synthetic rubbers derived from styrene and butadiene (the version developed by Goodyear is called Neolite). These materials have good abrasion resistance and good aging s ...

. Similar synergistic effect was seen in the vulcanization of natural rubber with hydrofuramide-sulfenamide activator where introduction of hydrofuramide reduced induction time, scorch time, and optimum cure time.

Raticide

Hydrofuramide has been found to be selectively toxic to rats. For all types of rats the lethal dose is 1 g/kg body weight. The chemical is less toxic to guinea pigs and has little or no toxicity to swine, dogs, cats or birds.

Food technology

Development of a pink color in a modified Badouin test, employing hydrofuramide, is diagnostic for adulteration of butter with cheap

hydrogenated vegetable oil Fat hydrogenation is the process of combining fat – typically liquid vegetable oils – with hydrogen, to convert some or all of the unsaturated fat into saturated fat, resulting in a solid or semi-solid fat. Changing the degree of saturation ...

References

{{Reflist, 2 2-Furyl compounds Imines