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E. J. Corey
Elias James Corey (born July 12, 1928) is an American organic chemist. In 1990, he won the Nobel Prize in Chemistry "for his development of the theory and methodology of organic synthesis", specifically retrosynthetic analysis. Regarded by many as one of the greatest living chemists, he has developed numerous synthetic reagents, methodologies and total syntheses and has advanced the science of organic synthesis considerably. Biography E.J. Corey (the surname was anglicized from Levantine Arabic ''Khoury'', meaning ''priest'') was born to Lebanese Greek Orthodox Christian immigrants Fatima (née Hasham) and Elias Corey in Methuen, Massachusetts, north of Boston. His mother changed his name from William to "Elias" to honor his father, who died eighteen months after Corey's birth. His widowed mother, brother, two sisters, aunt and uncle all lived together in a spacious house, struggling through the Great Depression. As a young boy, Corey was independent and enjoyed sports suc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methuen, Massachusetts
Methuen () is a 23 square mile (60 km2) city in Essex County, Massachusetts, United States. The population was 53,059 at the 2020 census. Methuen lies along the northwestern edge of Essex County, just east of Middlesex County and just south of Rockingham County, New Hampshire. The city is bordered by Haverhill to the northeast, North Andover to the southeast, Lawrence and Andover to the south, Dracut (Middlesex County) to the west, Pelham, New Hampshire ( Hillsborough County) to the northwest, and Salem, New Hampshire ( Rockingham County) to the north. Methuen is located southwest from Newburyport, north-northwest of Boston and south-southeast of Manchester, New Hampshire. History Methuen was first settled in 1642 and was officially incorporated in 1726. Methuen was originally part of Haverhill, Massachusetts. In 1724 Stephen Barker and others in the western part of that town petitioned the General Court to grant them permission to form a new town above Hawke's Meadow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gary H
Gary may refer to: *Gary (given name), a common masculine given name, including a list of people and fictional characters with the name *Gary, Indiana, the largest city named Gary Places ;Iran *Gary, Iran, Sistan and Baluchestan Province ;United States *Gary (Tampa), Florida * Gary, Maryland *Gary, Minnesota *Gary, South Dakota *Gary, West Virginia *Gary – New Duluth, a neighborhood in Duluth, Minnesota *Gary Air Force Base, San Marcos, Texas * Gary City, Texas Ships * USS ''Gary'' (DE-61), a destroyer escort launched in 1943 * USS ''Gary'' (CL-147), scheduled to be a light cruiser, but canceled prior to construction in 1945 * USS ''Gary'' (FFG-51), a frigate, commissioned in 1984 * USS ''Thomas J. Gary'' (DE-326), a destroyer escort commissioned in 1943 People and fictional characters * Gary (surname), including a list of people with the name *Gary (rapper), South Korean rapper and entertainer * Gary (Argentine singer), Argentine singer of cuarteto songs Other uses *'' Gar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corey–Gilman–Ganem Oxidation
In organic chemistry, an aldehyde () 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 common and play important roles in the technology and biological spheres. Structure and bonding Aldehydes feature a carbon center that is connected by a double bond to oxygen and a single bond to hydrogen and 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 C=O 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 are more soluble in water, formaldehyde and acetaldehyde completely so. The volatile aldehydes have pungent odors. Aldeh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corey–Fuchs Reaction
The Corey–Fuchs reaction, also known as the Ramirez–Corey–Fuchs reaction, is a series of chemical reactions designed to transform an aldehyde into an alkyne. The formation of the 1,1-dibromoolefins via phosphine-dibromomethylenes was originally discovered by Desai, McKelvie and Ramirez. The second step of the reaction to convert dibromoolefins to alkynes is known as Fritsch–Buttenberg–Wiechell rearrangement. The overall combined transformation of an aldehyde to an alkyne by this method is named after its developers, American chemists Elias James Corey and Philip L. Fuchs. By suitable choice of base, it is often possible to stop the reaction at the 1-bromoalkyne, a useful functional group for further transformation. Reaction mechanism The Corey–Fuchs reaction is based on a special case of the Wittig reaction, where two equivalents of triphenylphosphine are used with carbon tetrabromide to produce the triphenylphosphine-dibromomethylene ylide. This ylide undergoes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johnson–Corey–Chaykovsky Reaction
The Johnson–Corey–Chaykovsky reaction (sometimes referred to as the Corey–Chaykovsky reaction or CCR) is a chemical reaction used in organic chemistry for the synthesis of epoxides, aziridines, and cyclopropanes. It was discovered in 1961 by A. William Johnson and developed significantly by E. J. Corey and Michael Chaykovsky. The reaction involves addition of a sulfur ylide to a ketone, aldehyde, imine, or enone to produce the corresponding 3-membered ring. The reaction is diastereoselective favoring ''trans'' substitution in the product regardless of the initial stereochemistry. The synthesis of epoxides via this method serves as an important retrosynthetic alternative to the traditional epoxidation reactions of olefins. The reaction is most often employed for epoxidation via methylene transfer, and to this end has been used in several notable total syntheses (See Synthesis of epoxides below). Additionally detailed below are the history, mechanism, scope, and ena ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CBS Catalyst
The CBS catalyst or Corey–Bakshi–Shibata catalyst is an Chiral synthesis, asymmetric catalyst derived from proline. It finds many uses in organic reactions such as the CBS reduction, Diels-Alder reactions and (3+2) cycloadditions. Proline, a naturally occurring Optical isomerism, chiral compound, is readily and cheaply available. It transfers its stereocenter to the catalyst which in turn is able to drive an organic reaction selectively to one of two possible enantiomers. This selectivity is due to steric strain in the transition state that develops for one enantiomer but not for the other. Synthesis The CBS catalyst can be prepared from diphenylprolinol, condensed with a phenylboronic acid, or with borane (as shown below). The CBS catalyst then complexes ''in situ'' with borane to give the active catalyst. Use The general outline for the organic synthesis of a CBS catalyst is shown below. The first leg of the reaction sequence starts from the Azeotropic distill ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synthon
In retrosynthetic analysis, a synthon is a hypothetical unit within a target molecule that represents a potential starting reagent in the retroactive synthesis of that target molecule. The term was coined in 1967 by E. J. Corey. He noted in 1988 that the "word ''synthon'' has now come to be used to mean synthetic ''building block'' rather than retrosynthetic fragmentation structures". It was noted in 1998 that the phrase did not feature very prominently in Corey's 1981 book ''The Logic of Chemical Synthesis'', as it was not included in the index. Because synthons are charged, when placed into a synthesis a neutral form is found commercially instead of forming and using the potentially very unstable charged synthons. Example : In planning the synthesis of phenylacetic acid, two synthons are identified: a nucleophilic "COOH−" group, and an electrophilic "PhCH2+" group. Of course, both synthons do not exist per se; synthetic equivalents corresponding to the synthons are reacted ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retrosynthetic Analysis
Retrosynthetic analysis is a technique for solving problems in the planning of organic syntheses. This is achieved by transforming a target molecule into simpler precursor structures regardless of any potential reactivity/interaction with reagents. Each precursor material is examined using the same method. This procedure is repeated until simple or commercially available structures are reached. These simpler/commercially available compounds can be used to form a synthesis of the target molecule. E.J. Corey formalized this concept in his book ''The Logic of Chemical Synthesis''. The power of retrosynthetic analysis becomes evident in the design of a synthesis. The goal of retrosynthetic analysis is a structural simplification. Often, a synthesis will have more than one possible synthetic route. Retrosynthesis is well suited for discovering different synthetic routes and comparing them in a logical and straightforward fashion. A database may be consulted at each stage of the analysis, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jin-Quan Yu
Jin-Quan Yu () is a Chinese-born American chemist. He is the Frank and Bertha Hupp Professor of Chemistry at Scripps Research, where he also holds the Bristol Myers Squibb Endowed Chair in Chemistry. He is a 2016 recipient of the MacArthur Fellowship, and is a member of the American Academy of Arts and Sciences, American Association for the Advancement of Science, and the Royal Society of Chemistry. Yu is a leader in the development of C–H bond activation reactions in organic chemistry, and has reported many C–H activation reactions that could be applicable towards the synthesis of drug molecules and other biologically active compounds. He also co-founded Vividion Therapeutics in 2016 with fellow Scripps chemists Benjamin Cravatt and Phil Baran, and is a member of the scientific advisory board of Chemveda Life Sciences. Early life and education Yu was born on January 10, 1966 in Zhejiang, China. He received his B.Sc. in Chemistry at East China Normal University in 1987. Yu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ramakanth Sarabu
Ramakanth Sarabu (June 20, 1955 – February 11, 2021) was an Indian organic chemist. He is known for his contributions in diabetes research, specifically the work of Glucokinase activation as a treatment therapy for type 2 diabetes. Biography Ramakanth Sarabu was born in Hyderabad, Telangana where he received his early education. He earned a master's degree from Osmania University in Organic Chemistry and his doctorate from Indian Institute of Technology, Madras in Molecular Rearrangements from 1979 to 1984. In 1984 he moved to the US to pursue post-doctoral fellowship under Elias James Corey, at Harvard University. He did a second post-doctoral fellowship in 1985 at Case Western University in Cleveland, OH. He is known for his works and contributions in the domain of Glucokinase activation as a treatment therapy for type 2 diabetes. He died on 11 February 2021 in Montville, New Jersey, while serving as the Head of Chemistry at ''Cellarity''. Prior to that, from 1997 to 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hisashi Yamamoto
(born July 16, 1943) is a prominent organic chemist and currently a member of the faculty at the University of Chicago and professor of Chubu University. Life Born in Kobe, Japan, Yamamoto earned a B.S. at Kyoto University in 1967 and a Ph.D. at Harvard University in 1971. He was a professor at Nagoya University from 1983 until 2002 and has since been a professor within the Department of Chemistry at the University of Chicago. His research work is largely in the chemistry of acid catalysts that play an important role in triggering or driving chemical reactions, specifically Lewis and Brønsted acid catalysts used in selective organic synthesis. Yamamoto has authored or co-authored several books on topics in modern synthetic organic chemistry. As of 2021, his h-index equals to 120 with more than 64,000 citations. Awards and recognitions *1988 Japan IBM Science Prize *1992 Chu-Nichi Culture Prize *2002 Medals with Purple ribbon *2003 Fellow of the American Association for t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brian Stoltz
Brian M. Stoltz is currently a professor of chemistry at the California Institute of Technology. The primary focus of his research is chemical synthesis with an emphasis on expanding the scope of allylic alkylation for the preparation of complex molecules possessing unique structural, biological, and physical properties. His research involves the total synthesis of natural products such as dragmacidin F and (–)-cyanthiwigin F, and development of synthetic reactions to access quaternary stereocenters. Specifically, he has focused on the allylic alkylation of enolates, developing an enantioselective variant in 2004. Education Stoltz received undergraduate degrees in Chemistry and German from Indiana University of Pennsylvania in 1993. As an undergraduate he spent a year abroad at the Ludwig Maximilian University of Munich. He went on to earn his M.S. and Ph.D. at Yale University, where he studied organic chemistry under the supervision of John L. Wood, completing his studie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
