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Dipropyl Ether
Dipropyl ether is the symmetrical ether of two ''n''-propyl groups. It is a colorless, flammable liquid with a sweet odor typical of ethers. Preparation Acid catalyzed ether synthesis Dipropyl ether can be synthesized by reacting two molecules of ''n''-propanol in the presence of p-toluenesulfonic acid (a strong acid) and heat, in the same way other symmetrical ethers may be formed. Williamson ether synthesis This ether may also be prepared by way of the Williamson ether synthesis in which ''n''-propoxide, the conjugate base of ''n''-propanol, is reacted with an ''n''-propyl halide: : Safety As is typical of ethers, dipropyl ether may slowly form explosive organic peroxides over long periods in storage. Antioxidants such as butylated hydroxytoluene are often added to ethers to prevent this process. Due to the shock and light sensitive nature of organic peroxides, dipropyl ether should never be boiled or evaporated to dryness. This concentrates peroxides that may be prese ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ether
In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula , where R and R′ represent the alkyl or aryl groups. Ethers can again be classified into two varieties: if the alkyl or aryl groups are the same on both sides of the oxygen atom, then it is a simple or symmetrical ether, whereas if they are different, the ethers are called mixed or unsymmetrical ethers. A typical example of the first group is the solvent and anaesthetic diethyl ether, commonly referred to simply as "ether" (). Ethers are common in organic chemistry and even more prevalent in biochemistry, as they are common linkages in carbohydrates and lignin. Structure and bonding Ethers feature bent C–O–C linkages. In dimethyl ether, the bond angle is 111° and C–O distances are 141 pm. The barrier to rotation about the C–O bonds is low. The bonding of oxygen in ethers, alcohols, and water is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propyl
In organic chemistry, propyl is a three-carbon alkyl substituent with chemical formula for the linear form. This substituent form is obtained by removing one hydrogen atom attached to the terminal carbon of propane. A propyl substituent is often represented in organic chemistry with the symbol Pr (not to be confused with the element praseodymium). An isomeric form of propyl is obtained by moving the point of attachment from a terminal carbon atom to the central carbon atom, named 1-methylethyl or isopropyl. To maintain four substituents on each carbon atom, one hydrogen atom has to be moved from the middle carbon atom to the carbon atom which served as attachment point in the ''n''-propyl variant, written as . Linear propyl is sometimes termed normal and hence written with a prefix ''n''- (i.e., ''n-''propyl), as the absence of the prefix ''n''- does not indicate which attachment point is chosen, i.e. absence of prefix does not automatically exclude the possibility of it being ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flammable Liquid
A flammable liquid is a liquid which can be easily ignited in air at ambient temperatures, i.e. it has a flash point at or below nominal threshold temperatures defined by a number of national and international standards organisations. The Occupational Safety and Health Administration (OSHA) of the United States Department of Labor defines a liquid as flammable if it has a flash point at or below 199.4 °F (93 °C). Prior to bringing regulations in line with the United Nations Globally Harmonized System of Classification and Labeling of Chemicals (GHS) in 2012, OSHA considered flammable liquids to be those with a flash point below 100 °F (37.8 °C). Those with flash points above 100 °F and below 200 °F (93.3 °C) were classified as combustible liquids. Studies show that the actual measure of a liquid's flammability, its flash point, is dependent on altitude. Categorization Both OSHA and GHS further divide flammable liquids into 4 categories: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1-Propanol
Propan-1-ol (also propanol, n-propyl alcohol) is a primary alcohol with the formula and sometimes represented as PrOH or ''n''-PrOH. It is a colorless liquid and an isomer of 2-propanol. It is formed naturally in small amounts during many fermentation processes and used as a solvent in the pharmaceutical industry, mainly for resins and cellulose esters, and, sometimes, as a disinfecting agent. Chemical properties Propan-1-ol shows the normal reactions of a primary alcohol. Thus it can be converted to alkyl halides; for example red phosphorus and iodine produce n-propyl iodide in 80% yield, while with catalytic gives n-propyl chloride. Reaction with acetic acid in the presence of an catalyst under Fischer esterification conditions gives propyl acetate, while refluxing propanol overnight with formic acid alone can produce propyl formate in 65% yield. Oxidation of propan-1-ol with and gives a 36% yield of propionaldehyde, and therefore for this type of reaction higher yi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
P-toluenesulfonic Acid
''p''-Toluenesulfonic acid (PTSA or ''p''TsOH) or tosylic acid (TsOH) is an organic compound with the formula CH3 C6H4 SO3H. It is a white extremely hygroscopic solid that is soluble in water, alcohols, and other polar organic solvents. The CH3C6H4SO2 group is known as the tosyl group and is often abbreviated as Ts or Tos. Most often, TsOH refers to the monohydrate, TsOH.H2O. As with other aryl sulfonic acids, TsOH is a strong organic acid. It is about one million times stronger than benzoic acid. It is one of the few strong acids that is solid and therefore is conveniently weighed and stored. Preparation and uses TsOH is prepared on an industrial scale by the sulfonation of toluene. Common impurities include benzenesulfonic acid and sulfuric acid. TsOH monohydrate contains an amount of water. To estimate the total moisture present as impurity, the Karl Fischer method is used. Impurities can be removed by recrystallization from its concentrated aqueous solution followed by az ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Williamson Ether Synthesis
The Williamson ether synthesis is an organic reaction, forming an ether from an organohalide and a deprotonated alcohol ( alkoxide). This reaction was developed by Alexander Williamson in 1850. Typically it involves the reaction of an alkoxide ion with a primary alkyl halide via an SN2 reaction. This reaction is important in the history of organic chemistry because it helped prove the structure of ethers. The general reaction mechanism is as follows: An example is the reaction of sodium ethoxide with chloroethane to form diethyl ether and sodium chloride: :C2H5Cl + C2H5ONa -> C2H5OC2H5 + NaCl Mechanism The Williamson ether reaction follows an SN2 bimolecular nucleophilic substitution mechanism. In an SN2 reaction mechanism there is a backside attack of an electrophile by a nucleophile and it occurs in a concerted mechanism (happens all at once). In order for the SN2 reaction to take place there must be a good leaving group which is strongly electronegative, commonly a hali ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Williamson Ether Synthesis Of Dipropyl Ether
Williamson may refer to: Places *Williamson, Arizona *Williamson, Georgia *Williamson, Illinois * Williamson, Iowa *Williamson, New York, a town in Wayne County, New York. * Williamson (CDP), New York, a hamlet and census-designated place in Wayne County, New York. *Williamson, West Virginia *Williamson County, Illinois *Williamson County, Tennessee *Williamson County, Texas People *Williamson (surname) Other uses *'' Williamson v. Lee Optical Co.'', a 1955 U.S. Supreme Court case *Williamson amplifier, a type of push-pull audio amplifier with low distortion first designed in 1947 *Williamson Road Junior Public School, an elementary school in Toronto, Ontario *Williamson ether synthesis, one of the most common methods for preparing ethers See also *Williams (other) *Williamston (other) *Williamstown (other) *Justice Williamson (other) Justice Williamson * John Isaac Williamson, associate justice of the Supreme Court of Missouri * Robert B. Wil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Peroxide
In organic chemistry, organic peroxides are organic compounds containing the peroxide functional group (). If the R′ is hydrogen, the compounds are called hydroperoxides, which are discussed in that article. The O−O bond of peroxides easily breaks, producing free radicals of the form (the dot represents an unpaired electron). Thus, organic peroxides are useful as initiators for some types of polymerisation, such as the epoxy resins used in glass-reinforced plastics. MEKP and benzoyl peroxide are commonly used for this purpose. However, the same property also means that organic peroxides can explosively combust. Organic peroxides, like their inorganic counterparts, are often powerful bleaching agents. Types of organic peroxides Tert-Butyl hydroperoxide Structural Formula V2.svg, ''tert''-Butyl hydroperoxide, a hydroperoxide (formula: ROOH) that is used to epoxide alkenes. Dicumyl peroxide.svg, Dicumyl peroxide, a dialkyl peroxide (formula: ROOR) that is used to initiate p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Butylated Hydroxytoluene
Butylated hydroxytoluene (BHT), also known as dibutylhydroxytoluene, is a lipophilic organic compound, chemically a derivative of phenol, that is useful for its antioxidant properties. BHT is widely used to prevent free radical-mediated oxidation in fluids (e.g. fuels, oils) and other materials, and the regulations overseen by the U.S. F.D.A.—which considers BHT to be " generally recognized as safe"—allow small amounts to be added to foods. Despite this, and the earlier determination by the National Cancer Institute that BHT was noncarcinogenic in an animal model, societal concerns over its broad use have been expressed. BHT has also been postulated as an antiviral drug, but as of December 2022 , use of BHT as a drug is not supported by the scientific literature and it has not been approved by any drug regulatory agency for use as an antiviral. Natural occurrence Phytoplankton, including the green algae ''Botryococcus braunii'', as well as three different cyanobacteria ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sigma-Aldrich
Sigma-Aldrich (formally MilliporeSigma) is an American chemical, life science, and biotechnology company that is owned by the German chemical conglomerate Merck Group. Sigma-Aldrich was created in 1975 by the merger of Sigma Chemical Company and Aldrich Chemical Company. It grew through various acquisitions until it had over 9,600 employees and was listed on the Fortune 1000. The company is headquartered in St. Louis and has operations in approximately 40 countries. In 2015, the German chemical conglomerate Merck Group acquired Sigma-Aldrich for $17 billion. The company is currently a part of Merck's life science business and in combination with Merck's earlier acquired Millipore Corporation, Millipore, operates as MilliporeSigma. History Sigma Chemical Company of St. Louis and Aldrich Chemical Company of Milwaukee were both American specialty chemical companies when they merged in August 1975. The company grew throughout the 1980s and 1990s, with significant expansion in fac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canadian Centre For Occupational Health And Safety
The Canadian Centre for Occupational Health and Safety (CCOHS) is an independent departmental corporation under Schedule II of the Financial Administration Act and is accountable to Parliament through the Minister of Labour. CCOHS functions as the primary national agency in Canada for the advancement of safe and healthy workplaces and preventing work-related injuries, illnesses and deaths. Additional work in this area is carried out by provincial and territorial labour departments and workers' compensation. CCOHS was created in 1978 by an Act of Parliament ''Canadian Centre for Occupational Health and Safety Act'' S.C., 1977-78, c. 29 The act was based on the belief that all Canadians had "…a fundamental right to a healthy and safe working environment". The centre, located in Hamilton, Ontario, is governed by a tripartite Council of Governors representing government (federal, provincial and territorial), employers, and workers. CCOHS promotes the total well-being—ph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diisopropyl Ether
Diisopropyl ether is secondary ether that is used as a solvent. It is a colorless liquid that is slightly soluble in water, but miscible with organic solvents. It is used as an extractant and an oxygenate gasoline additive. It is obtained industrially as a byproduct in the production of isopropanol by hydration of propylene. Diisopropyl ether is sometimes represented by the abbreviation DIPE. Uses Whereas at 20 °C, diethyl ether will dissolve 1% by weight water, diisopropyl ether only dissolves 0.88%. Diisopropyl ether is used as a specialized solvent to remove or extract polar organic compounds from aqueous solutions, e.g. phenols, ethanol, acetic acid. It has also been used as an antiknock agent. In the laboratory, diisopropyl ether is useful for recrystallizations because it has a wide liquid range. Diisopropyl ether is used for converting bromoboranes, which are thermally labile, into isopropoxy derivatives. Safety Diisopropyl ether forms explosive peroxides upon stand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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