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Piperic Acid
Piperic acid is a chemical often obtained by the base-hydrolysis of the alkaloid piperine from black pepper, followed by acidification of the corresponding salt. Piperic acid is an intermediate in the synthesis of other compounds such as piperonal, and as-such may be used to produce fragrances, perfumes flavorants and drugs as well as other useful compounds. Preparation Piperic acid can be prepared from the commercially-available alkaloid piperine, a cyclic amide containing a piperidine group, by reacting it with a hydroxide such as potassium hydroxide, then acidifying the formed piperate salt with hydrochloric acid or another acid. The toxic compound piperidine is given off during the base-hydrolysis of piperine and as-such, safety precautions should be taken. : Reactions Reaction of piperic acid with strong oxidizers such as potassium permanganate or ozone, or a halogen such as bromine followed by sodium hydroxide causes oxidative cleavage of the double-bonds, yielding piperona ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Base (chemistry)
In chemistry, there are three definitions in common use of the word base, known as Arrhenius bases, Brønsted bases, and Lewis bases. All definitions agree that bases are substances that react with acids, as originally proposed by G.-F. Rouelle in the mid-18th century. In 1884, Svante Arrhenius proposed that a base is a substance which dissociates in aqueous solution to form Hydroxide ions OH−. These ions can react with hydrogen ions (H+ according to Arrhenius) from the dissociation of acids to form water in an acid–base reaction An acid–base reaction is a chemical reaction that occurs between an acid and a base. It can be used to determine pH via titration. Several theoretical frameworks provide alternative conceptions of the reaction mechanisms and their applica .... A base was therefore a metal hydroxide such as Sodium hydroxide, NaOH or Calcium hydroxide, Ca(OH)2. Such aqueous hydroxide solutions were also described by certain characteristic properties. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isosafrole
Isosafrole is an organic compound that is used in the fragrance industry. Structurally, the molecule is related to phenylpropene, a type of aromatic organic chemical. Its fragrance is reminiscent of anise or licorice. It is found in small amounts in various essential oils, but is most commonly obtained by isomerizing the plant oil safrole. It exists as two geometric isomers, ''cis''-isosafrole and ''trans''-isosafrole. Isosafrole is a precursor to the important fragrance piperonal.Karl-Georg Fahlbusch, Franz-Josef Hammerschmidt, Johannes Panten, Wilhelm Pickenhagen, Dietmar Schatkowski, Kurt Bauer, Dorothea Garbe and Horst Surburg "Flavors and Fragrances" in ''Ullmann's Encyclopedia of Industrial Chemistry'', Wiley-VCH, Weinheim, 2003. It can also be converted via the intermediate compound MDP2P into the psychoactive drug MDMA 3,4-Methylenedioxymethamphetamine (MDMA), commonly seen in Tablet (pharmacy), tablet form (ecstasy) and crystal form (molly or mandy), i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Safrole
Safrole is an organic compound with the formula CH2O2C6H3CH2CH=CH2. It is a colorless oily liquid, although impure samples can appear yellow. A member of the phenylpropanoid family of natural products, it is found in sassafras plants, among others. Small amounts are found in a wide variety of plants, where it functions as a natural antifeedant. ''Ocotea pretiosa'', which grows in Brazil, and ''Sassafras albidum'', which grows in eastern North America, are the main natural sources of safrole. It has a characteristic "sweet-shop" aroma. It is a precursor in the synthesis of the insecticide synergist piperonyl butoxide, the fragrance piperonal via isosafrole, and the empathogenic/entactogenic substance MDMA. History Safrole was obtained from a number of plants, but especially from the sassafras tree (''Sassafras albidum''), which is native to North America, and from Japanese star anise (''Illicium anisatum'', called ''shikimi'' in Japan). In 1844, the French chemist Édouard ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piperine
Piperine, along with its isomer chavicine, is the alkaloid responsible for the pungency of black pepper and long pepper. It has been used in some forms of traditional medicine. Preparation Due to its poor solubility in water, piperine is typically extracted from black pepper by using organic solvents like dichloromethane. The amount of piperine varies from 1–2% in long pepper, to 5–10% in commercial white and black peppers. Piperine can also be prepared by treating a concentrated alcoholic extract of black pepper with an alcoholic solution of potassium hydroxide to remove resin (said to contain chavicine, an isomer of piperine). The solution is decanted from the insoluble residue and left to stand overnight. During this period, the alkaloid slowly crystallizes from the solution. Piperine has been synthesized by the action of piperonoyl chloride on piperidine. Reactions Piperine forms salts only with strong acids. The platinichloride B4·H2PtCl6 forms orange-red needles ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piperonal
Piperonal, also known as heliotropin, is an organic compound which is commonly found in fragrances and flavors.Karl-Georg Fahlbusch, Franz-Josef Hammerschmidt, Johannes Panten, Wilhelm Pickenhagen, Dietmar Schatkowski, Kurt Bauer, Dorothea Garbe and Horst Surburg "Flavors and Fragrances" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2003. The molecule is structurally related to other aromatic aldehydes such as benzaldehyde and vanillin. Natural occurrence Piperonal naturally occurs in various plants. Examples include dill, vanilla, Viola odorata, violet flowers, and black pepper. Preparation Piperonal can be prepared by the oxidative cleavage of isosafrole or by using a multistep sequence from catechol or 1,3-Benzodioxole, 1,2-methylenedioxybenzene. Synthesis from the latter chemical is accomplished through a condensation reaction with glyoxylic acid followed by Bond cleavage, cleaving the resulting Alpha hydroxy acid, α-hydroxy acid with an oxidizin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amalgam (chemistry)
An amalgam is an alloy of mercury with another metal A metal (from Greek μέταλλον ''métallon'', "mine, quarry, metal") is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. Metals are typicall .... It may be a liquid, a soft paste or a solid, depending upon the proportion of mercury. These alloys are formed through metallic bonding, with the electrostatic attractive force of the conduction electrons working to bind all the positively charged metal ions together into a Crystal structure, crystal lattice structure. Almost all metals can form amalgams with mercury, the notable exceptions being iron, platinum, tungsten, and tantalum. Silver-mercury amalgam (dentistry), amalgams are important in dentistry, and gold-mercury amalgam is used in the Gold extraction, extraction of gold from ore. Dentistry has used alloys of mercury with metals such as silver, copper, indium, tin a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidative Cleavage
Organic reductions or organic oxidations or organic redox reactions are redox reactions that take place with organic compounds. In organic chemistry oxidations and reductions are different from ordinary redox reactions, because many reactions carry the name but do not actually involve electron transfer.March Jerry; (1985). Advanced Organic Chemistry reactions, mechanisms and structure (3rd ed.). New York: John Wiley & Sons, inc. Instead the relevant criterion for organic oxidation is gain of oxygen and/or loss of hydrogen, respectively.''Organic Redox Systems: Synthesis, Properties, and Applications'', Tohru Nishinaga 2016 Simple functional groups can be arranged in order of increasing oxidation state. The oxidation numbers are only an approximation: When methane is oxidized to carbon dioxide its oxidation number changes from −4 to +4. Classical reductions include alkene reduction to alkanes and classical oxidations include oxidation of alcohols to aldehydes. In oxidations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Hydroxide
Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations and hydroxide anions . Sodium hydroxide is a highly caustic base and alkali that decomposes proteins at ordinary ambient temperatures and may cause severe chemical burns. It is highly soluble in water, and readily absorbs moisture and carbon dioxide from the air. It forms a series of hydrates . The monohydrate crystallizes from water solutions between 12.3 and 61.8 °C. The commercially available "sodium hydroxide" is often this monohydrate, and published data may refer to it instead of the anhydrous compound. As one of the simplest hydroxides, sodium hydroxide is frequently used alongside neutral water and acidic hydrochloric acid to demonstrate the pH scale to chemistry students. Sodium hydroxide is used in many industries: in the manufacture of pulp and paper, textiles, drinking water, soaps and deterge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
