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Scott E. Denmark
Scott Eric Denmark is an American chemist who is the Reynold C. Fuson Professor of Chemistry at the University of Illinois at Urbana-Champaign (UIUC). Denmark received an bachelor's degree, S.B. degree from Massachusetts Institute of Technology, MIT in 1975 and the D.Sc.Tech. degree from ETH Zurich in 1980, under the supervision of Professor Albert Eschenmoser. He joined the faculty at UIUC the same year and became an associate professor in 1986, full professor in 1987, and was named the Fuson Professor of Chemistry in 1991. He served as the president and editor-in-chief of the ''Organic Reactions'' book series between 2008 and 2018. In 2017, Denmark was elected to the American Academy of Arts and Sciences. In 2018, he was elected to the National Academy of Sciences. Early life and education Denmark was born in Lynbrook, New York in 1953. He attended MIT as an undergraduate and during his studies he was involved in research with both Richard H. Holm on ferredoxin analogs and Dani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New York (state)
New York, officially the State of New York, is a state in the Northeastern United States. It is often called New York State to distinguish it from its largest city, New York City. With a total area of , New York is the 27th-largest U.S. state by area. With 20.2 million people, it is the fourth-most-populous state in the United States as of 2021, with approximately 44% living in New York City, including 25% of the state's population within Brooklyn and Queens, and another 15% on the remainder of Long Island, the most populous island in the United States. The state is bordered by New Jersey and Pennsylvania to the south, and Connecticut, Massachusetts, and Vermont to the east; it has a maritime border with Rhode Island, east of Long Island, as well as an international border with the Canadian provinces of Quebec to the north and Ontario to the northwest. New York City (NYC) is the most populous city in the United States, and around two-thirds of the state's populat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ETH Zurich
(colloquially) , former_name = eidgenössische polytechnische Schule , image = ETHZ.JPG , image_size = , established = , type = Public , budget = CHF 1.896 billion (2021) , rector = Günther Dissertori , president = Joël Mesot , academic_staff = 6,612 (including doctoral students, excluding 527 professors of all ranks, 34% female, 65% foreign nationals) (full-time equivalents 2021) , administrative_staff = 3,106 (40% female, 19% foreign nationals, full-time equivalents 2021) , students = 24,534 (headcount 2021, 33.3% female, 37% foreign nationals) , undergrad = 10,642 , postgrad = 8,299 , doctoral = 4,460 , other = 1,133 , address = Rämistrasse 101CH-8092 ZürichSwitzerland , city = Zürich , coor = , campus = Urban , language = German, English (Masters and upwards, sometimes Bachelor) , affiliations = CESAER, EUA, GlobalTech, IARU, IDEA League, UNITECH , website ethz.ch, colors = Black and White , logo = ETH Zürich Logo black.svg ETH Z� ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phase-transfer Catalyst
In chemistry, a phase-transfer catalyst or PTC is a catalyst that facilitates the transition of a reactant from one phase into another phase where reaction occurs. Phase-transfer catalysis is a special form of heterogeneous catalysis. Ionic reactants are often soluble in an aqueous phase but insoluble in an organic phase in the absence of the phase-transfer catalyst. The catalyst functions like a detergent for solubilizing the salts into the organic phase. Phase-transfer catalysis refers to the acceleration of the reaction upon the addition of the phase-transfer catalyst. By using a PTC process, one can achieve faster reactions, obtain higher conversions or yields, make fewer byproducts, eliminate the need for expensive or dangerous solvents that will dissolve all the reactants in one phase, eliminate the need for expensive raw materials and/or minimize waste problems. Phase-transfer catalysts are especially useful in green chemistry—by allowing the use of water, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aldol Reaction
The aldol reaction is a means of forming carbon–carbon bonds in organic chemistry. Discovered independently by the Russian chemist Alexander Borodin in 1869 and by the French chemist Charles-Adolphe Wurtz in 1872, the reaction combines two carbonyl compounds (the original experiments used aldehydes) to form a new β-hydroxy carbonyl compound. These products are known as '' aldols'', from the ''ald''ehyde + alcoh''ol'', a structural motif seen in many of the products. Aldol structural units are found in many important molecules, whether naturally occurring or synthetic. For example, the aldol reaction has been used in the large-scale production of the commodity chemical pentaerythritol and the synthesis of the heart disease drug Lipitor ( atorvastatin, calcium salt). The aldol reaction unites two relatively simple molecules into a more complex one. Increased complexity arises because up to two new stereogenic centers (on the α- and β-carbon of the aldol adduct, marked w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitroalkene
A nitroalkene, or nitro olefin, is a functional group combining the functionality of its constituent parts, an alkene and nitro group, while displaying its own chemical properties through alkene activation, making the functional group useful in specialty reactions such as the Michael reaction or Diels-Alder additions. Synthesis Nitroalkenes are synthesized by various means, notable examples include: * Nitroaldol reactions such as the Henry reaction: : * Nitration of an alkene with nitryl iodide generated ''in-situ'' from silver nitrite and elemental iodine: * Direct nitration of alkenes with nitric oxide and an aluminum oxide catalyst in acidic conditions: *Direct nitration of alkenes with Clayfen ( Iron(III) nitrate supported on Montmorillonite clay): * Dehydration of nitro-alcohols: Reactions Nitroalkenes are useful intermediates for various chemical functionalities. * A nitroalkene behaving as a Michael acceptor in the synthesis of Lycoricidine: * Nitroalkene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frederick Stanley Kipping
Frederic Stanley Kipping FRS (16 August 1863 – 1 May 1949) was an English chemist. He undertook much of the pioneering work on silicon polymers and coined the term silicone. Life He was born in Salford, Lancashire, England, the son of James Kipping, a Bank of England official, and Julia Du Val, a daughter of painter Charles Allen Du Val. He was educated at Manchester Grammar School before enrolling in 1879 at Owens College (now Manchester University) for an external degree from the University of London. After working for the local gas company for a short time he went in 1886 to Germany to work under William Henry Perkin, Jr. in the laboratories of Adolf von Baeyer at Munich University. Back in England, he took a position as demonstrator for Perkin, who had been appointed professor at Heriot-Watt College, Edinburgh. In 1890, Kipping was appointed chief demonstrator in chemistry for the City and Guilds of London Institute, where he worked for the chemist Henry Edward ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Claisen Rearrangement
The Claisen rearrangement is a powerful carbon–carbon bond-forming chemical reaction discovered by Rainer Ludwig Claisen. The heating of an allyl vinyl ether will initiate a ,3sigmatropic rearrangement to give a γ,δ-unsaturated carbonyl, driven by exergonically favored carbonyl CO bond formation (ΔΔHf = -327kcalmol−1). Mechanism The Claisen rearrangement is an exothermic, concerted (bond cleavage and recombination) pericyclic reaction. Woodward–Hoffmann rules show a suprafacial, stereospecific reaction pathway. The kinetics are of the first order and the whole transformation proceeds through a highly ordered cyclic transition state and is intramolecular. Crossover experiments eliminate the possibility of the rearrangement occurring via an intermolecular reaction mechanism and are consistent with an intramolecular process. There are substantial solvent effects observed in the Claisen rearrangement, where polar solvents tend to accelerate the reaction to a gre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nazarov Cyclization Reaction
The Nazarov cyclization reaction (often referred to as simply the Nazarov cyclization) is a chemical reaction used in organic chemistry for the synthesis of cyclopentenones. The reaction is typically divided into ''classical'' and ''modern'' variants, depending on the reagents and substrates employed. It was originally discovered by Ivan Nikolaevich Nazarov (1906–1957) in 1941 while studying the rearrangements of allyl vinyl ketones. As originally described, the Nazarov cyclization involves the activation of a divinyl ketone using a stoichiometric Lewis acid or protic acid promoter. The key step of the reaction mechanism involves a cationic 4π- electrocyclic ring closure which forms the cyclopentenone product (See Mechanism below). As the reaction has been developed, variants involving substrates other than divinyl ketones and promoters other than Lewis acids have been subsumed under the name Nazarov cyclization provided that they follow a similar mechanistic pathway. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclophane
In organic chemistry, a cyclophane is a hydrocarbon consisting of an aromatic unit (typically a benzene ring) and a chain that forms a bridge between two non-adjacent positions of the aromatic ring. More complex derivatives with multiple aromatic units and bridges forming cagelike structures are also known. Cyclophanes are well-studied examples of strained organic compounds. Cyclophanes Structures Paracyclophanes adopt the boat conformation normally observed in cyclohexanes. Smaller value of n lead to greater distortions. X-ray crystallography on ' aracyclophane' shows that the aromatic bridgehead carbon atom makes an angle of 20.5° with the plane. The benzyl carbons deviate by another 20.2°. The carbon-to-carbon bond length alternation has increased from 0 for benzene to 39 pm. Despite their distorted structures, cyclophanes retain their aromaticity, as determined by UV-vis spectroscopy. Reactivity With regards to their reactivity, cyclophanes often exhibit diene-lik ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daniel S
Daniel is a masculine given name and a surname of Hebrew origin. It means "God is my judge"Hanks, Hardcastle and Hodges, ''Oxford Dictionary of First Names'', Oxford University Press, 2nd edition, , p. 68. (cf. Gabriel—"God is my strength"), and derives from two early biblical figures, primary among them Daniel from the Book of Daniel. It is a common given name for males, and is also used as a surname. It is also the basis for various derived given names and surnames. Background The name evolved into over 100 different spellings in countries around the world. Nicknames ( Dan, Danny) are common in both English and Hebrew; "Dan" may also be a complete given name rather than a nickname. The name "Daniil" (Даниил) is common in Russia. Feminine Femininity (also called womanliness) is a set of attributes, behaviors, and roles generally associated with women and girls. Femininity can be understood as socially constructed, and there is also some evidence th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferredoxin
Ferredoxins (from Latin ''ferrum'': iron + redox, often abbreviated "fd") are iron–sulfur proteins that mediate electron transfer in a range of metabolic reactions. The term "ferredoxin" was coined by D.C. Wharton of the DuPont Co. and applied to the "iron protein" first purified in 1962 by Mortenson, Valentine, and Carnahan from the anaerobic bacterium '' Clostridium pasteurianum''. Another redox protein, isolated from spinach chloroplasts, was termed "chloroplast ferredoxin". The chloroplast ferredoxin is involved in both cyclic and non-cyclic photophosphorylation reactions of photosynthesis. In non-cyclic photophosphorylation, ferredoxin is the last electron acceptor thus reducing the enzyme NADP+ reductase. It accepts electrons produced from sunlight- excited chlorophyll and transfers them to the enzyme ferredoxin: NADP+ oxidoreductase . Ferredoxins are small proteins containing iron and sulfur atoms organized as iron–sulfur clusters. These biological " capacitors" ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Richard H
Richard is a male given name. It originates, via Old French, from Old Frankish and is a compound of the words descending from Proto-Germanic ''*rīk-'' 'ruler, leader, king' and ''*hardu-'' 'strong, brave, hardy', and it therefore means 'strong in rule'. Nicknames include " Richie", "Dick", " Dickon", " Dickie", "Rich", " Rick", " Rico", " Ricky", and more. Richard is a common English, German and French male name. It's also used in many more languages, particularly Germanic, such as Norwegian, Danish, Swedish, Icelandic, and Dutch, as well as other languages including Irish, Scottish, Welsh and Finnish. Richard is cognate with variants of the name in other European languages, such as the Swedish "Rickard", the Catalan "Ricard" and the Italian "Riccardo", among others (see comprehensive variant list below). People named Richard Multiple people with the same name * Richard Andersen (other) * Richard Anderson (other) * Richard Cartwright (disambiguati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
