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Heptanal
Heptanal or heptanaldehyde is an alkyl aldehyde. It is a colourless liquid with a strong fruity odor, which is used as precursor to components in perfumes and lubricants. Production The formation of heptanal in the fractional distillation of castor oil was already described in 1878. The large-scale production is based on the pyrolytic cleavage of ricinoleic acid (Arkema method) and on the hydroformylation of 1-hexene with rhodium 2-ethylhexanoate as a catalyst upon addition of some 2-ethylhexanoic acid (Oxea method): Heptanal naturally occurs in the essential oils of ylang-ylang (''Cananga odorata''), clary sage (''Salvia sclarea''), lemon ('' Citrus x limon''), bitter orange ('' Citrus x aurantium''), rose ( ''Rosa'') and hyacinth ( ''Hyacinthus'').G. A. Burdock, ''Fenaroli’s Handbook of Flavor Ingredients, Fifth Edition'', 2005, CRC Press, Boca Raton, Fl., . Properties Heptanal is a flammable, slightly volatile colorless liquid of pervasive fruity to oily-greasy odor, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jasminaldehyde
Jasminaldehyde (also known as jasmine aldehyde and α-pentylcinnamaldehyde) is a fine chemical used as an aroma compound in perfumes. It is responsible for jasmine's characteristic scent. Synthesis Jasminaldehyde used in industry is commonly derived not from jasmine essential oil, but ultimately from the castor bean plant. The process starts with ricinoleic acid, the principal constituent of castor oil. This compound undergoes cracking to undecylenic acid (used mainly to produce Nylon 11) and heptanal. The heptanal, once distilled, is then reacted with benzaldehyde in the presence of a basic catalyst (''trans''-aldol condensation) to give jasminaldehyde and water. The foul-smelling 2-pentylnon-2-enal is an unwanted byproduct that results from the self-condensation of heptanal.G. A. Burdock, ''Fenaroli’s Handbook of Flavor Ingredients, Fifth Edition'', 2005, CRC Press, Boca Raton, Fl., This process parallels the preparation hexyl cinnamaldehyde from octanal Octanal is t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heptanoic Acid
Enanthic acid, also called heptanoic acid, is an organic compound composed of a seven-carbon chain terminating in a carboxylic acid functional group. It is a colorless oily liquid with an unpleasant, rancid odor. It contributes to the odor of some rancid oils. It is slightly soluble in water, but very soluble in ethanol and ether. Salts and esters of enanthic acid are called enanthates or heptanoates. Its name derives from the Latin '' oenanthe'' which is in turn derived from the Ancient Greek ''oinos'' "wine" and ''anthos'' "blossom." Production The methyl ester of ricinoleic acid, obtained from castor bean oil, is the main commercial precursor to enanthic acid. It is pyrolyzed to the methyl ester of 10-undecenoic acid and heptanal, which is then air-oxidized to the carboxylic acid. Approximately 20,000 tons were consumed in Europe and US in 1980.David J. Anneken, Sabine Both, Ralf Christoph, Georg Fieg, Udo Steinberner, Alfred Westfechtel "Fatty Acids" in Ullmann's Encycloped ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Castor Oil
Castor oil is a vegetable oil pressed from castor beans. It is a colourless or pale yellow liquid with a distinct taste and odor. Its boiling point is and its density is 0.961 g/cm3. It includes a mixture of triglycerides in which about 90% of fatty acids are ricinoleates. Oleic acid and linoleic acid are the other significant components. Castor oil and its derivatives are used in the manufacturing of soaps, lubricants, hydraulic and brake fluids, paints, dyes, coatings, inks, cold-resistant plastics, waxes and polishes, nylon, and perfumes. Etymology The name probably comes from a confusion between the ''Ricinus'' plant that produces it and another plant, the ''Vitex agnus-castus''. An alternative etymology, though, suggests that it was used as a replacement for castoreum. Composition Castor oil is well known as a source of ricinoleic acid, a monounsaturated, 18-carbon fatty acid. Among fatty acids, ricinoleic acid is unusual in that it has a hydroxyl functional gro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexanal
Hexanal, also called hexanaldehyde or caproaldehyde is an alkyl aldehyde used in the flavor industry to produce fruity flavors. Its scent resembles freshly cut grass Poaceae () or Gramineae () is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos and the grasses of natural grassland and species cultivated in lawns a ..., like ''cis''-3-hexenal. It is potentially useful as a natural extract that prevents fruit spoilage. It occurs naturally, and contributes to a hay-like "off-note" flavor in green peas. The first synthesis of hexanal was published in 1907 by P. Bagard. / American Chemical Society References [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miscibility
Miscibility () is the property of two substances to mix in all proportions (that is, to fully dissolve in each other at any concentration), forming a homogeneous mixture (a solution). The term is most often applied to liquids but also applies to solids and gases. For example, water and ethanol are miscible because they mix in all proportions. By contrast, substances are said to be immiscible if there are certain proportions in which the mixture does not form a solution. For one example, oil is not soluble in water, so these two solvents are immiscible. As another example, butanone (methyl ethyl ketone) is significantly soluble in water, but these two solvents are also immiscible because in some proportions the mixture will separate into two phases. Organic compounds In organic compounds, the weight percent of hydrocarbon chain often determines the compound's miscibility with water. For example, among the alcohols, ethanol has two carbon atoms and is miscible with water, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Knaevenagel Reaction
In organic chemistry, the Knoevenagel condensation () reaction is a type of chemical reaction named after German chemist Emil Knoevenagel. It is a modification of the aldol condensation. A Knoevenagel condensation is a nucleophilic addition of an active hydrogen compound to a carbonyl group followed by a dehydration reaction in which a molecule of water is eliminated (hence '' condensation''). The product is often an α,β-unsaturated ketone (a conjugated enone). In this reaction the carbonyl group is an aldehyde or a ketone. The catalyst is usually a weakly basic amine. The active hydrogen component has the form * or for instance diethyl malonate, Meldrum's acid, ethyl acetoacetate or malonic acid, or cyanoacetic acid. * , for instance nitromethane. where Z is an electron withdrawing group. Z must be powerful enough to facilitate deprotonation to the enolate ion even with a mild base. Using a strong base in this reaction would induce self-condensation of the alde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds. Oxygen is Earth's most abundant element, and after hydrogen and helium, it is the third-most abundant element in the universe. At standard temperature and pressure, two atoms of the element bind to form dioxygen, a colorless and odorless diatomic gas with the formula . Diatomic oxygen gas currently constitutes 20.95% of the Earth's atmosphere, though this has changed considerably over long periods of time. Oxygen makes up almost half of the Earth's crust in the form of oxides.Atkins, P.; Jones, L.; Laverman, L. (2016).''Chemical Principles'', 7th edition. Freeman. Many major classes of organic molecules in living organisms contain oxygen atoms, such as proteins, nucleic acids, carbohydrates, and fats, as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 Saturated and unsaturated compounds, saturate organic compounds. Hydrogenation typically constitutes the addition of pairs of hydrogen atoms to a molecule, often an alkene. Catalysts are required for the reaction to be usable; non-catalytic hydrogenation takes place only at very high temperatures. Hydrogenation reduces Double bond, double and Triple bond, triple bonds in hydrocarbons. Process Hydrogenation has three components, the Saturated and unsaturated compounds, unsaturated substrate, the hydrogen (or hydrogen source) and, invariably, a catalyst. The redox, reduction reaction is carried out at different temperatures and pressures depending upon the substrate and the activity of the catalyst. Related or competing reactions The same ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1-Heptanol
1-Heptanol is an alcohol with a seven carbon chain and the structural formula of CH3(CH2)6OH. It is a clear colorless liquid that is very slightly soluble in water, but miscible with ether and ethanol. Overview There are three other isomers of heptanol that have a straight chain, 2-heptanol, 3-heptanol, and 4-heptanol, which differ by the location of the alcohol functional group. Heptanol is commonly used in cardiac electrophysiology experiments to block gap junctions and increase axial resistance between myocytes. Increasing axial resistance will decrease conduction velocity and increase the heart's susceptibility to reentrant excitation and sustained arrhythmias. 1-Heptanol has a pleasant smell and is used in cosmetics for its fragrance. See also * 2-Heptanol * 3-Heptanol 3-Heptanol or heptan-3-ol is an organic alcohol with the chemical formula C7H16O. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ignition Temperature
The autoignition temperature or kindling point of a substance is the lowest temperature in which it spontaneously ignites in a normal atmosphere without an external source of ignition, such as a flame or spark. This temperature is required to supply the activation energy needed for combustion. The temperature at which a chemical ignites decreases as the pressure is increased. *The ignition temperature of a substance is the lowest temperature at which the substance starts combustion. *Substances which spontaneously ignite in a normal atmosphere at naturally ambient temperatures are termed pyrophoric. Autoignition temperatures of liquid chemicals are typically measured using a flask placed in a temperature-controlled oven in accordance with the procedure described in ASTM E659. When measured for plastics, autoignition temperature can be also measured under elevated pressure and at 100% oxygen concentration. The resulting value is used as a predictor of viability for high-oxy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lower Explosion Limit
Mixtures of dispersed combustible materials (such as gaseous or vaporised fuels, and some dusts) and oxygen in the air will burn only if the fuel concentration lies within well-defined lower and upper bounds determined experimentally, referred to as flammability limits or explosive limits. Combustion can range in violence from deflagration through detonation. Limits vary with temperature and pressure, but are normally expressed in terms of volume percentage at 25 °C and atmospheric pressure. These limits are relevant both in producing and optimising explosion or combustion, as in an engine, or to preventing it, as in uncontrolled explosions of build-ups of combustible gas or dust. Attaining the best combustible or explosive mixture of a fuel and air (the stoichiometric proportion) is important in internal combustion engines such as Petrol engine, gasoline or diesel engines. The standard reference work is still that elaborated by Michael George Zabetakis, a fire safety enginee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
