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Virgil Boekelheide
Virgil Boekelheide (28 July 1919 – 24 September 2003) was an American organic chemist and a professor in the department of chemistry at the University of Oregon. He is known for his work on aromatic compounds, particularly cyclophanes, and a name reaction, the Boekelheide reaction, is named after him. Education and academic career Boekelheide was born in Chelsea, South Dakota to a family of German ancestry. He received his bachelor's degree from Dakota Wesleyan University in 1939. He then received his PhD from the University of Minnesota in 1943, where he worked under the supervision of C. Frederick Koelsch. After three years as an instructor at the University of Illinois, he joined the faculty as a professor at the University of Rochester in 1946. He moved to the University of Oregon in 1960 and remained there for the rest of his research career. He retired in 1984. Boekelheide was awarded the Guggenheim Fellowship in 1953 and was an Alexander von Humboldt Fellow, permitting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chelsea, South Dakota
Chelsea is a town in Faulk County, South Dakota, United States. The population was 19 at the 2020 census. The town was named after Chelsea, London, perhaps via Chelsea, Massachusetts. Geography Chelsea is located at (45.167611, -98.740673). According to the United States Census Bureau, the town has a total area of , all land. The town was founded in 1906. Demographics 2010 census As of the census of 2010, there were 27 people, 13 households, and 8 families residing in the town. The population density was . There were 15 housing units at an average density of . The racial makeup of the town was 100.0% White. There were 13 households, of which 30.8% had children under the age of 18 living with them, 46.2% were married couples living together, 7.7% had a female householder with no husband present, 7.7% had a male householder with no wife present, and 38.5% were non-families. 38.5% of all households were made up of individuals, and 30.8% had someone living alone who was 65 y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexander Von Humboldt Fellow
The Alexander von Humboldt Foundation (german: Alexander von Humboldt-Stiftung) is a foundation established by the government of the Federal Republic of Germany and funded by the Federal Foreign Office, the Federal Ministry of Education and Research, the Federal Ministry for Economic Cooperation and Development as well as other national and international partners; it promotes international academic cooperation between excellent scientists and scholars from Germany and from abroad. Description Every year, the Foundation grants more than 700 competitive research fellowships and awards, primarily going to academics from natural sciences ( mathematics included) and the humanities. It allows scientists and scholars from all over the world to come to Germany to work on a research project they have chosen themselves together with a host and collaborative partner. Additionally it funds German scholars' via the Feodor Lynen Fellowships to go anywhere in the world to work on a research p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1919 Births
Events January * January 1 ** The Czechoslovak Legions occupy much of the self-proclaimed "free city" of Pressburg (now Bratislava), enforcing its incorporation into the new republic of Czechoslovakia. ** HMY ''Iolaire'' sinks off the coast of the Hebrides; 201 people, mostly servicemen returning home to Lewis and Harris, are killed. * January 2– 22 – Russian Civil War: The Red Army's Caspian-Caucasian Front begins the Northern Caucasus Operation against the White Army, but fails to make progress. * January 3 – The Faisal–Weizmann Agreement is signed by Emir Faisal (representing the Arab Kingdom of Hejaz) and Zionist leader Chaim Weizmann, for Arab–Jewish cooperation in the development of a Jewish homeland in Palestine, and an Arab nation in a large part of the Middle East. * January 5 – In Germany: ** Spartacist uprising in Berlin: The Marxist Spartacus League, with the newly formed Communist Party of Germany and the Independent Social D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Chemists
Organic may refer to: * Organic, of or relating to an organism, a living entity * Organic, of or relating to an anatomical organ Chemistry * Organic matter, matter that has come from a once-living organism, is capable of decay or is the product of decay, or is composed of organic compounds * Organic compound, a compound that contains carbon ** Organic chemistry, chemistry involving organic compounds Farming, certification and products * Organic farming, agriculture conducted according to certain standards, especially the use of stated methods of fertilization and pest control * Organic certification, accreditation process for producers of organically-farmed products * Organic horticulture, the science and art of growing fruits, vegetables, flowers, or ornamental plants by following the essential principles of organic agriculture * Organic products, "organics": ** Organic food, food produced from organic farming methods and often certified organic according to organic farming sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Chemists
American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, people who self-identify their ancestry as "American" ** American English, the set of varieties of the English language native to the United States ** Native Americans in the United States, indigenous peoples of the United States * American, something of, from, or related to the Americas, also known as "America" ** Indigenous peoples of the Americas * American (word), for analysis and history of the meanings in various contexts Organizations * American Airlines, U.S.-based airline headquartered in Fort Worth, Texas * American Athletic Conference, an American college athletic conference * American Recordings (record label), a record label previously known as Def American * American University, in Washington, D.C. Sports teams Soccer * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Patron Of The Arts
Patronage is the support, encouragement, privilege, or financial aid that an organization or individual bestows on another. In the history of art, arts patronage refers to the support that kings, popes, and the wealthy have provided to artists such as musicians, painters, and sculptors. It can also refer to the right of bestowing offices or church benefices, the business given to a store by a regular customer, and the guardianship of saints. The word "patron" derives from the la, patronus ("patron"), one who gives benefits to his clients (see Patronage in ancient Rome). In some countries the term is used to describe political patronage or patronal politics, which is the use of state resources to reward individuals for their electoral support. Some patronage systems are legal, as in the Canadian tradition of the Prime Minister to appoint senators and the heads of a number of commissions and agencies; in many cases, these appointments go to people who have supported the politica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pi-stacking
In chemistry, pi stacking (also called π–π stacking) refers to the presumptive attractive, noncovalent pi interactions (orbital overlap) between the pi bonds of aromatic rings. However this is a misleading description of the phenomena since direct stacking of aromatic rings (the "sandwich interaction") is electrostatically repulsive. What is more commonly observed (see figure to the right) is either a staggered stacking (parallel displaced) or pi-teeing (perpendicular T-shaped) interaction both of which are electrostatic attractive For example, the most commonly observed interactions between aromatic rings of amino acid residues in proteins is a staggered stacked followed by a perpendicular orientation. Sandwiched orientations are relatively rare. Pi stacking is repulsive as it places carbon atoms with partial negative charges from one ring on top of other partial negatively charged carbon atoms from the second ring and hydrogen atoms with partial positive charges on top of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superphane
.2.2.2.2.21,2,3,4,5,6)Cyclophane or superphane is a 6-fold bridged cyclophane with all arene positions in the benzene dimer taken up by ethylene spacers. The compound has been of some scientific interest as a model for testing aromaticity and was first synthesised by Virgil Boekelheide in 1979. Superphane is the base compound for a large group of derivatives with structural variations. The analogs with 2 to 5 bridges are also known compounds. The benzene rings have been replaced by other aromatic units, such as those based on ferrocene or stabilized cyclobutadiene. Numerous derivatives are known with variations in the type and length of the bridging units. Synthesis The first synthesis of superphane itself by Boekelheide involved forming pairs of bridging units. At each stage, two ''o''-chloromethyl toluene structures are pyrolyzed to form ''o''-xylylenes, either directly or via benzocyclobutene intermediates. Upon further pyrolysis, these each undergo electrocyclic ring-opening ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Synthesis
Organic synthesis is a special branch of chemical synthesis and is concerned with the intentional construction of organic compounds. Organic molecules are often more complex than inorganic compounds, and their synthesis has developed into one of the most important branches of organic chemistry. There are several main areas of research within the general area of organic synthesis: '' total synthesis'', '' semisynthesis'', and ''methodology''. Total synthesis A total synthesis is the complete chemical synthesis of complex organic molecules from simple, commercially available petrochemical or natural precursors. Total synthesis may be accomplished either via a linear or convergent approach. In a ''linear'' synthesis—often adequate for simple structures—several steps are performed one after another until the molecule is complete; the chemical compounds made in each step are called synthetic intermediates. Most often, each step in a synthesis refers to a separate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bridged Compound
In chemistry, a bicyclic molecule () is a molecule that features two joined rings. Bicyclic structures occur widely, for example in many biologically important molecules like α-thujene and camphor. A bicyclic compound can be carbocyclic (all of the ring atoms are carbons), or heterocyclic (the rings' atoms consist of at least two elements), like DABCO. Moreover, the two rings can both be aliphatic (''e.g.'' decalin and norbornane), or can be aromatic (''e.g.'' naphthalene), or a combination of aliphatic and aromatic (''e.g.'' tetralin). Three modes of ring junction are possible for a bicyclic compound: * In spirocyclic compounds, the two rings share only one single atom, the spiro atom, which is usually a quaternary carbon. An example of a spirocyclic compound is the photochromic switch spiropyran. * In fused/condensed bicyclic compounds, two rings share two adjacent atoms. In other words, the rings share one covalent bond, ''i.e.'' the so-called bridgehead atoms are directl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aromaticity
In chemistry, aromaticity is a chemical property of cyclic (ring-shaped), ''typically'' planar (flat) molecular structures with pi bonds in resonance (those containing delocalized electrons) that gives increased stability compared to saturated compounds having single bonds, and other geometric or connective non-cyclic arrangements with the same set of atoms. Aromatic rings are very stable and do not break apart easily. Organic compounds that are not aromatic are classified as aliphatic compounds—they might be cyclic, but only aromatic rings have enhanced stability. The term ''aromaticity'' with this meaning is historically related to the concept of having an aroma, but is a distinct property from that meaning. Since the most common aromatic compounds are derivatives of benzene (an aromatic hydrocarbon common in petroleum and its distillates), the word ''aromatic'' occasionally refers informally to benzene derivatives, and so it was first defined. Nevertheless, man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Product
A natural product is a natural compound or substance produced by a living organism—that is, found in nature. In the broadest sense, natural products include any substance produced by life. Natural products can also be prepared by chemical synthesis (both semisynthesis and total synthesis) and have played a central role in the development of the field of organic chemistry by providing challenging synthetic targets. The term natural product has also been extended for commercial purposes to refer to cosmetics, dietary supplements, and foods produced from natural sources without added artificial ingredients. Within the field of organic chemistry, the definition of natural products is usually restricted to organic compounds isolated from natural sources that are produced by the pathways of primary or secondary metabolism. Within the field of medicinal chemistry, the definition is often further restricted to secondary metabolites. Secondary metabolites (or specialized metabo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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