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Phellandrene
Phellandrenes are a pair of organic compounds that have a similar molecular structure and similar chemical properties. α-Phellandrene and β-phellandrene are cyclic monoterpenes and are double-bond isomers. In α-phellandrene, both double bonds are endocyclic and in β-phellandrene, one of them is exocyclic. Both are insoluble in water, but miscible with ether. α-Phellandrene was named after ''Eucalyptus phellandra'', now called ''Eucalyptus radiata'', from which it can be isolated. It is also a constituent of the essential oil of ''Eucalyptus dives''. β-Phellandrene has been isolated from the oil of water fennel and Canada balsam oil. The phellandrenes are used in fragrances because of their pleasing aromas. The odor of β-phellandrene has been described as peppery-minty and slightly citrusy. The α-phellandrene isomer can form hazardous and explosive peroxides on contact with air at elevated temperatures. Biosynthesis The biosynthesis of phellandrene begins with dim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phellandrene Mechanism
Phellandrenes are a pair of organic compounds that have a similar molecular structure and similar chemical properties. α-Phellandrene and β-phellandrene are cyclic terpene, monoterpenes and are double-bond isomers. In α-phellandrene, both double bonds are endocyclic and in β-phellandrene, one of them is exocyclic. Both are insoluble in water, but miscibility, miscible with diethyl ether, ether. α-Phellandrene was named after ''Eucalyptus phellandra'', now called ''Eucalyptus radiata'', from which it can be isolated. It is also a constituent of the essential oil of ''Eucalyptus dives''. β-Phellandrene has been isolated from the oil of fennel, water fennel and Canada balsam oil. The phellandrenes are used in fragrances because of their pleasing aromas. The odor of β-phellandrene has been described as peppery-minty and slightly citrusy. The α-phellandrene isomer can form hazardous and explosive peroxides on contact with air at elevated temperatures. Biosynthesis The b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eucalyptus Dives
''Eucalyptus dives'', commonly known as the broad-leaved peppermint or blue peppermint, is a species of tree that is endemic to south-eastern Australia. It has rough, finely fibrous bark on the trunk and larger branches, smooth bark above, lance-shaped or curved adult leaves, flower buds in groups of eleven or more, white flowers and cup-shaped, hemispherical or conical fruit. Description ''Eucalyptus dives'' is a tree that grows to a height of and forms a lignotuber. The bark on the trunk and larger branches is rough, finely fibrous and greyish and smooth grey on the thinner branches. Young plants and coppice regrowth have leaves arranged in opposite pairs, egg-shaped to heart-shaped or curved, long and wide and sessile. Adult leaves are arranged alternately, lance-shaped to curved, the same slightly glossy or dull green on both sides, long and wide on a petiole long. The flower buds are usually arranged in groups of eleven or more in leaf axils on an unbranched peduncle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eucalyptus Radiata
''Eucalyptus radiata'', commonly known as the narrow-leaved peppermint or Forth River peppermint, is a species of tree that is endemic to south-eastern Australia. It has rough, fibrous to flaky bark on the trunk and larger branches, smooth grey bark on the thinner branches, lance-shaped to curved or almost linear leaves, flower buds in groups of eleven to twenty or more, white flowers and cup-shaped, hemispherical or shortened spherical fruit. Description ''Eucalyptus radiata'' is a tree that typically grows to a height of and forms a lignotuber. It has rough, finely fibrous or flaky grey bark on the trunk and branches, usually smooth grey bark on branches thinner than . Young plants and coppice regrowth have sessile, narrow lance-shaped to linear leaves that are long, wide, paler on the lower surface and arranged in opposite pairs. Adult leaves are the same shade of green on both sides, lance-shaped to curved or almost linear, long and wide, tapering to a petiole long. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Merck Index
''The Merck Index'' is an encyclopedia of chemicals, drugs and biologicals with over 10,000 monograph on single substances or groups of related compounds published online by the Royal Society of Chemistry. History The first edition of the Merck's Index was published in 1889 by the German chemical company Emanuel Merck and was primarily used as a sales catalog for Merck's growing list of chemicals it sold. The American subsidiary was established two years later and continued to publish it. During World War I the US government seized Merck's US operations and made it a separate American "Merck" company that continued to publish the Merck Index. In 2012 the Merck Index was licensed to the Royal Society of Chemistry. An online version of The Merck Index, including historic records and new updates not in the print edition, is commonly available through research libraries. It also includes an appendix with monographs on organic named reactions. The 15th edition was published in Apr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SN1 Reaction
The SN1 reaction is a substitution reaction in organic chemistry, the name of which refers to the Hughes-Ingold symbol of the mechanism. "SN" stands for "nucleophilic substitution", and the "1" says that the rate-determining step is unimolecular. Thus, the rate equation is often shown as having first-order dependence on the substrate and zero-order dependence on the nucleophile. This relationship holds for situations where the amount of nucleophile is much greater than that of the intermediate. Instead, the rate equation may be more accurately described using steady-state kinetics. The reaction involves a carbocation intermediate and is commonly seen in reactions of secondary or tertiary alkyl halides under strongly basic conditions or, under strongly acidic conditions, with secondary or tertiary alcohols. With primary and secondary alkyl halides, the alternative SN2 reaction occurs. In inorganic chemistry, the SN1 reaction is often known as the ''dissociative substitution''. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoterpenes
Monoterpenes are a class of terpenes that consist of two isoprene units and have the molecular formula C10H16. Monoterpenes may be linear (acyclic) or contain rings (monocyclic and bicyclic). Modified terpenes, such as those containing oxygen functionality or missing a methyl group, are called monoterpenoids. Monoterpenes and monoterpenoids are diverse. They have relevance to the pharmaceutical, cosmetic, agricultural, and food industries. Biosynthesis Monoterpenes are derived biosynthetically from units of isopentenyl pyrophosphate, which is formed from acetyl-CoA via the intermediacy of mevalonic acid in the HMG-CoA reductase pathway. An alternative, unrelated biosynthesis pathway of IPP is known in some bacterial groups and the plastids of plants, the so-called MEP-(2-methyl-D-erythritol-4-phosphate) pathway, which is initiated from Pentose, C5 sugars. In both pathways, IPP is isomerized to DMAPP by the enzyme isopentenyl pyrophosphate isomerase. Geranyl pyrophosphate is the pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perfume Ingredients
Perfume (, ; french: parfum) is a mixture of fragrant essential oils or aroma compounds (fragrances), fixatives and solvents, usually in liquid form, used to give the human body, animals, food, objects, and living-spaces an agreeable scent. The 1939 Nobel Laureate for Chemistry, Leopold Ružička stated in 1945 that "right from the earliest days of scientific chemistry up to the present time, perfumes have substantially contributed to the development of organic chemistry as regards methods, systematic classification, and theory." Ancient texts and archaeological excavations show the use of perfumes in some of the earliest human civilizations. Modern perfumery began in the late 19th century with the commercial synthesis of aroma compounds such as vanillin or coumarin, which allowed for the composition of perfumes with smells previously unattainable solely from natural aromatics. History The word ''perfume'' derives from the Latin ''perfumare'', meaning "to smoke through" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrocarbons
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odors are usually weak or exemplified by the odors of gasoline and lighter fluid. They occur in a diverse range of molecular structures and phases: they can be gases (such as methane and propane), liquids (such as hexane and benzene), low melting solids (such as paraffin wax and naphthalene) or polymers (such as polyethylene and polystyrene). In the fossil fuel industries, ''hydrocarbon'' refers to the naturally occurring petroleum, natural gas and coal, and to their hydrocarbon derivatives and purified forms. Combustion of hydrocarbons is the main source of the world's energy. Petroleum is the dominant raw-material source for organic commodity chemicals such as solvents and polymers. Most anthropogenic (human-generated) emissions of greenhouse gases are carb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elimination Reaction
An elimination reaction is a type of organic reaction in which two substituents are removed from a molecule in either a one- or two-step mechanism. The one-step mechanism is known as the E2 reaction, and the two-step mechanism is known as the E1 reaction. The numbers refer not to the number of steps in the mechanism, but rather to the kinetics of the reaction: E2 is bimolecular (second-order) while E1 is unimolecular (first-order). In cases where the molecule is able to stabilize an anion but possesses a poor leaving group, a third type of reaction, E1CB, exists. Finally, the pyrolysis of xanthate and acetate esters proceed through an "internal" elimination mechanism, the Ei mechanism. E2 mechanism The E2 mechanism, where E2 stands for bimolecular elimination, involves a one-step mechanism in which ''carbon-hydrogen'' and ''carbon-halogen'' bonds break to form a double bond (''C=C Pi bond''). The specifics of the reaction are as follows: * E2 is a single step elimination, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allyl Group
In organic chemistry, an allyl group is a substituent with the structural formula , where R is the rest of the molecule. It consists of a methylene bridge () attached to a vinyl group (). The name is derived from the scientific name for garlic, . In 1844, Theodor Wertheim isolated an allyl derivative from garlic oil and named it "". The term allyl applies to many compounds related to , some of which are of practical or of everyday importance, for example, allyl chloride. Allylation is any chemical reaction that adds an allyl group to a substrate. Nomenclature A site adjacent to the unsaturated carbon atom is called the allylic position or allylic site. A group attached at this site is sometimes described as allylic. Thus, "has an allylic hydroxyl group". Allylic C−H bonds are about 15% weaker than the C−H bonds in ordinary sp3 carbon centers and are thus more reactive. Benzylic and allylic are related in terms of structure, bond strength, and reactivity. Other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geranyl Pyrophosphate
Geranyl pyrophosphate (GPP), also known as geranyl diphosphate (GDP), is the pyrophosphate ester of the terpenoid geraniol. Its salts are colorless. It is a precursor to many natural products. Occurrence GPP is an intermediate in the isoprenoid biosynthesis pathway that produces longer prenyl chains such as farnesyl pyrophosphate and geranylgeranyl pyrophosphate as well as many terpenes. It can be prepared in the laboratory from geraniol. Related compounds * Geraniol * Farnesyl pyrophosphate * Geranylgeranyl pyrophosphate See also * Dimethylallyltranstransferase Dimethylallyltranstransferase (DMATT), also known as farnesylpyrophosphate synthase (FPPS) or as farnesyldiphosphate synthase (FDPS), is an enzyme that in humans is encoded by the FDPS gene and catalyzes the transformation of dimethylallylpyr ... References Further reading *Kulkarni RS, Pandit SS, Chidley HG, Nagel R, Schmidt A, Gershenzon J, Pujari KH, Giri AP and Gupta VS, 2013Characterization of three n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
