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Hexanal
Hexanal, also called hexanaldehyde or caproaldehyde is an alkyl In organic chemistry, an alkyl group is an alkane missing one hydrogen. The term ''alkyl'' is intentionally unspecific to include many possible substitutions. An acyclic alkyl has the general formula of . A cycloalkyl group is derived from a cy ... aldehyde used in the flavor industry to produce fruity flavors. Its scent resembles freshly cut grass, 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] |
Oxford University
The University of Oxford is a collegiate research university in Oxford, England. There is evidence of teaching as early as 1096, making it the oldest university in the English-speaking world and the second-oldest continuously operating university globally. It expanded rapidly from 1167, when Henry II prohibited English students from attending the University of Paris. When disputes erupted between students and the Oxford townspeople, some Oxford academics fled northeast to Cambridge, where they established the University of Cambridge in 1209. The two English ancient universities share many common features and are jointly referred to as ''Oxbridge''. The University of Oxford comprises 43 constituent colleges, consisting of 36 semi-autonomous colleges, four permanent private halls and three societies (colleges that are departments of the university, without their own royal charter). and a range of academic departments that are organised into four divisions. Each college ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentanal
Pentanal (also called valeraldehyde) is the organic compound with molecular formula . Classified as an alkyl aldehyde, it is a colorless volatile liquid. Its odor is described as fermented, bready, fruity, nutty, berry. Production Pentanal is obtained by hydroformylation of butene. Also C4 mixtures can be used as starting material like the so-called raffinate II, which is produced by steam cracking and contains (''Z'')- and (''E'')-2-butene, 1-butene, butane and isobutane. The conversion to the product is accomplished with synthesis gas in the presence of a catalyst consisting of a rhodium-bisphosphite complex and a sterically hindered secondary amine with a selectivity toward pentanal of at least 90%. Use Pentanal undergoes the reactions characteristic of any alkyl aldehyde, i.e., oxidations, condensations, and reductions. 2-Octanone, produced for use in the fragrance industry, is obtained by the condensation of acetone and pentanal, followed by hydrogenation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkyl
In organic chemistry, an alkyl group is an alkane missing one hydrogen. The term ''alkyl'' is intentionally unspecific to include many possible substitutions. An acyclic alkyl has the general formula of . A cycloalkyl group is derived from a cycloalkane by removal of a hydrogen atom from a Ring (chemistry), ring and has the general formula . Typically an alkyl is a part of a larger molecule. In structural formulae, the symbol R is used to designate a generic (unspecified) alkyl group. The smallest alkyl group is methyl, with the formula . Related concepts Alkylation is the addition of alkyl groups to molecules, often by alkylating agents such as Haloalkane, alkyl halides. Alkylating antineoplastic agents are a class of compounds that are used to treat cancer. In such case, the term alkyl is used loosely. For example, nitrogen mustards are well-known alkylating agents, but they are not simple hydrocarbons. In chemistry, alkyl is a group, a substituent, that is attached to ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aldehyde
In organic chemistry, an aldehyde () (lat. ''al''cohol ''dehyd''rogenatum, dehydrogenated alcohol) is an organic compound containing a functional group with the structure . The functional group itself (without the "R" side chain) can be referred to as an aldehyde but can also be classified as a formyl group. Aldehydes are a common motif in many chemicals important in technology and biology. Structure and bonding Aldehyde molecules have a central carbon atom that is connected by a double bond to oxygen, a single bond to hydrogen and another single bond to a third substituent, which is carbon or, in the case of formaldehyde, hydrogen. The central carbon is often described as being sp2- hybridized. The aldehyde group is somewhat polar. The bond length is about 120–122 picometers. Physical properties and characterization Aldehydes have properties that are diverse and that depend on the remainder of the molecule. Smaller aldehydes such as formaldehyde and acetaldehyde are solubl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smell Of Freshly Cut Grass
The smell of freshly cut grass is an odour caused by green leaf volatiles (GLVs) released when it is damaged. Mechanical damage to grass from activities such as Lawn mower, lawnmowing results in the release of cis-3-Hexenal, ''cis''-3-hexenal and other compounds that contribute to a grassy or "green" smell. ''cis''-3-Hexenal has a low Odor detection threshold, odour detection threshold that humans can perceive at concentrations as low as 0.25 parts per billion. The GLVs responsible for the smell of freshly cut grass play a role in plant communication and plant defense against herbivory, plant defence against herbivory, functioning as a distress signal warning other plants of imminent danger and, in some instances, as a way to attract predators of grass-eating insects. For humans, the smell of freshly cut grass is connected through olfactory memory to past experiences involving the odour and may evoke nostalgia, eliciting associations with spring or summer. Chemical composition W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cis-3-Hexenal
''cis''-3-Hexenal, also known as (''Z'')-3-hexenal and leaf aldehyde, is an organic compound with the formula CH3CH2CH=CHCH2CHO. It is classified as an unsaturated aldehyde. It is a colorless liquid and an aroma compound with an intense odor of freshly cut grass and leaves. Occurrence It is one of the major volatile compounds in ripe tomatoes, although it tends to isomerize into the conjugated ''trans''-2-hexenal. It is produced in small amounts by most plants and it acts as an attractant to many predatory insects. It is also a pheromone in many insect species. See also * ''cis''-3-Hexen-1-ol has a similar but weaker odor and is used in flavors and perfumes. * 1-Hexanol, another volatile organic compound Volatile organic compounds (VOCs) are organic compounds that have a high vapor pressure at room temperature. They are common and exist in a variety of settings and products, not limited to Indoor mold, house mold, Upholstery, upholstered furnitur ..., also considered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CBC News
CBC News is the division of the Canadian Broadcasting Corporation responsible for the news gathering and production of news programs on the corporation's English-language operations, namely CBC Television, CBC Radio, CBC News Network, and CBC.ca. Founded in 1941 by the public broadcaster, CBC News is the largest news broadcaster in Canada and has local, regional, and national broadcasts and stations. It frequently collaborates with its organizationally separate French-language counterpart, Radio-Canada Info. History The first CBC newscast was a bilingual radio report on November 2, 1936. The CBC News Service was inaugurated during World War II on January 1, 1941, when Dan McArthur, chief news editor, had Wells Ritchie prepare for the announcer Charles Jennings a national report at 8:00 pm. Previously, CBC relied on The Canadian Press to provide it with wire copy for its news bulletins. Readers who followed Jennings were Lorne Greene, Frank Herbert and Earl Cameron. '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Synthesis
Organic synthesis is a branch of chemical synthesis concerned with the construction of organic compounds. Organic compounds are molecules consisting of combinations of covalently-linked hydrogen, carbon, oxygen, and nitrogen atoms. Within the general subject of organic synthesis, there are many different types of synthetic routes that can be completed including total synthesis, Enantioselective synthesis, stereoselective synthesis, automated synthesis, and many more. Additionally, in understanding organic synthesis it is necessary to be familiar with the methodology, techniques, and applications of the subject. Total synthesis A total synthesis refers to the complete chemical synthesis of molecules from simple, Precursor (chemistry), natural precursors. Total synthesis is accomplished either via a linear or convergent approach. In a Linear synthesis, ''linear'' synthesis—often adequate for simple structures—several steps are performed sequentially until the molecule is com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
