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In organic chemistry, the ene reaction is a chemical reaction between an alkene with an allylic hydrogen and a compound containing a multiple bond, in order to form a new σ-bond with migration of the ene double bond and 1,5 hydrogen shift. The product is a substituted alkene with the double bond shifted to the allylic position.
The Sandmeyer reaction is a chemical reaction used to synthesize aryl halides from aryl diazonium salts using copper salts as reagents or catalysts. It is an example of a radical-nucleophilic aromatic substitution. The Sandmeyer reaction provides a method through which one can perform unique transformations on benzene, such as halogenation, cyanation, trifluoromethylation, and hydroxylation.
The Hiyama coupling is a palladium-catalyzed cross-coupling reaction of organosilanes with organic halides used in organic chemistry to form carbon–carbon bonds. This reaction was discovered in 1988 by Tamejiro Hiyama and Yasuo Hatanaka as a method to form carbon-carbon bonds synthetically with chemo- and regioselectivity. The Hiyama coupling has been applied to the synthesis of various natural products.
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 catalysis and can act through homogeneous catalysis or heterogeneous catalysis methods depending on the catalyst used. 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.
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An oxaziridine is an organic molecule that features a three-membered heterocycle containing oxygen, nitrogen, and carbon. In their largest application, oxaziridines are intermediates in the industrial production of hydrazine. Oxaziridine derivatives are also used as specialized reagents in organic chemistry for a variety of oxidations, including alpha hydroxylation of enolates, epoxidation and aziridination of olefins, and other heteroatom transfer reactions. Oxaziridines also serve as precursors to amides and participate in [3+2] cycloadditions with various heterocumulenes to form substituted five-membered heterocycles. Chiral oxaziridine derivatives effect asymmetric oxygen transfer to prochiral enolates as well as other substrates. Some oxaziridines also have the property of a high barrier to inversion of the nitrogen, allowing for the possibility of chirality at the nitrogen center.
Melanie Sarah Sanford is an American chemist, currently the Moses Gomberg Distinguished University Professor of Chemistry and Arthur F. Thurnau Professor of Chemistry at the University of Michigan. She is a Fellow for the American Association for the Advancement of Science, and was elected a member of the National Academy of Sciences and the American Academy of Arts and Sciences in 2016. She has served as an executive editor of the Journal of the American Chemical Society since 2021, having been an associate editor of the since 2014.
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The White–Chen catalyst is an Iron-based coordination complex named after Professor M. Christina White and her graduate student Mark S. Chen. The catalyst is used along with hydrogen peroxide and acetic acid additive to oxidize aliphatic sp3 C-H bonds in organic synthesis. The catalyst is the first to allow for preparative and predictable aliphatic C–H oxidations over a broad range of organic substrates. Oxidations with the catalyst have proven to be remarkably predictable based on sterics, electronics, and stereoelectronics allowing for aliphatic C–H bonds to be thought of as a functional group in the streamlining of organic synthesis.
Metal-catalyzed C–H borylation reactions are transition metal catalyzed organic reactions that produce an organoboron compound through functionalization of aliphatic and aromatic C–H bonds and are therefore useful reactions for carbon–hydrogen bond activation. Metal-catalyzed C–H borylation reactions utilize transition metals to directly convert a C–H bond into a C–B bond. This route can be advantageous compared to traditional borylation reactions by making use of cheap and abundant hydrocarbon starting material, limiting prefunctionalized organic compounds, reducing toxic byproducts, and streamlining the synthesis of biologically important molecules. Boronic acids, and boronic esters are common boryl groups incorporated into organic molecules through borylation reactions. Boronic acids are trivalent boron-containing organic compounds that possess one alkyl substituent and two hydroxyl groups. Similarly, boronic esters possess one alkyl substituent and two ester groups. Boronic acids and esters are classified depending on the type of carbon group (R) directly bonded to boron, for example alkyl-, alkenyl-, alkynyl-, and aryl-boronic esters. The most common type of starting materials that incorporate boronic esters into organic compounds for transition metal catalyzed borylation reactions have the general formula (RO)2B-B(OR)2. For example, bis(pinacolato)diboron (B2Pin2), and bis(catecholato)diborane (B2Cat2) are common boron sources of this general formula.
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Pentamethylcyclopentadienyl rhodium dichloride dimer is an organometallic compound with the formula [(C5(CH3)5RhCl2)]2, commonly abbreviated [Cp*RhCl2]2 This dark red air-stable diamagnetic solid is a reagent in organometallic chemistry.
In organic chemistry, hydrovinylation is the formal insertion of an alkene into the C-H bond of ethylene. The more general reaction, hydroalkenylation, is the formal insertion of an alkene into the C-H bond of any terminal alkene. The reaction is catalyzed by metal complexes. A representative reaction is the conversion of styrene and ethylene to 3-phenybutene:
Chao-Jun "C.-J." Li is E. B. Eddy Professor of Chemistry and Canada Research Chair in Green Chemistry at McGill University, Montréal. He works on organic transformation applied to Green chemistry, including C-H activation, reactions in water and photochemistry.
Richmond Sarpong is a Ghanaian-American chemist who is a professor at the University of California, Berkeley. Sarpong works on natural product total synthesis to better understand biological systems and allow for the development of novel therapeutics. He was awarded a Guggenheim Fellowship in 2017, and was elected a fellow of the American Academy of Arts and Sciences in 2020. He serves on the editorial boards of Organic Syntheses, Accounts of Chemical Research and Synlett.
Miyaura borylation, also known as the Miyaura borylation reaction, is a named reaction in organic chemistry that allows for the generation of boronates from vinyl or aryl halides with the cross-coupling of bis(pinacolato)diboron in basic conditions with a catalyst such as PdCl2(dppf). The resulting borylated products can be used as coupling partners for the Suzuki reaction.
Alison Wendlandt is an American chemist who is an assistant professor at the Massachusetts Institute of Technology. Her research considers the development of catalysts for organic synthesis.
In organic chemistry, carboboration describes an addition of both a carbon and a boron moiety to certain carbon-containing double and triple bonds, such as alkenes, alkynes, and allenes.
References
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- ↑ "Alison Narayan". University of Michigan. Retrieved 22 February 2019.
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- ↑ Hay, Michael B.; Hardin, Alison R.; Wolfe, John P. (2005). "Palladium-Catalyzed Synthesis of Tetrahydrofurans from γ-Hydroxy Terminal Alkenes: Scope, Limitations, and Stereoselectivity". The Journal of Organic Chemistry. 70 (8): 3099–3107. doi:10.1021/jo050022+. ISSN 0022-3263. PMC 2700004 . PMID 15822970.
- ↑ Narayan, Alison Rae Hardin (2011). New Reactions and Synthetic Strategies toward Indolizidine Alkaloids and Pallavicinia Diterpenes (Thesis). UC Berkeley.
- ↑ "The Sarpong Group Homepage". Synthetic organic chemistry lab at UC Berkeley. Archived from the original on 2020-03-31. Retrieved 2020-03-31.
- 1 2 Sarpong, Richmond; Narayan, Alison R. Hardin (2012-01-07). "Indolizinones as synthetic scaffolds: fundamental reactivity and the relay of stereochemical information". Organic & Biomolecular Chemistry. 10 (1): 70–78. doi:10.1039/C1OB06423A. ISSN 1477-0539. PMC 3342682 . PMID 22072189.
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- 1 2 Negretti, Solymar; Narayan, Alison R. H.; Chiou, Karoline C.; Kells, Petrea M.; Stachowski, Jessica L.; Hansen, Douglas A.; Podust, Larissa M.; Montgomery, John; Sherman, David H. (2014-04-02). "Directing Group-Controlled Regioselectivity in an Enzymatic C–H Bond Oxygenation". Journal of the American Chemical Society. 136 (13): 4901–4904. doi:10.1021/ja5016052. ISSN 0002-7863. PMC 4012894 . PMID 24627965.
- ↑ Narayan, Alison R. H.; Jiménez-Osés, Gonzalo; Liu, Peng; Negretti, Solymar; Zhao, Wanxiang; Gilbert, Michael M.; Ramabhadran, Raghunath O.; Yang, Yun-Fang; Furan, Lawrence R.; Li, Zhe; Podust, Larissa M. (2015). "Enzymatic hydroxylation of an unactivated methylene C–H bond guided by molecular dynamics simulations". Nature Chemistry. 7 (8): 653–660. Bibcode:2015NatCh...7..653N. doi:10.1038/nchem.2285. ISSN 1755-4349. PMC 4518477 . PMID 26201742.
- ↑ "A year in the life of a new professor". cen.acs.org. Retrieved 2019-01-27.
- ↑ "How bacteria build a deadly toxin". Nature. 554 (7693): 407. 2018-02-19. Bibcode:2018Natur.554U.407.. doi: 10.1038/d41586-018-02199-4 . PMID 32094965.
- ↑ "2019 Awardees - Thieme Chemistry - Georg Thieme Verlag". Thieme. Retrieved 2019-01-27.
- ↑ "RCSA Names Two Dozen 2019 Cottrell Scholars". Research Corporation for Science Advancement. Retrieved 2019-02-11.
- ↑ "2019 Fellows". sloan.org. Archived from the original on 2019-02-20. Retrieved 2019-02-19.
- ↑ "2020 Camille Dreyfus Teacher-Scholar Awards". Dreyfus Foundation. 2020-04-27. Retrieved 2021-06-10.
- ↑ Sherman, David H.; Houk, K. N.; Montgomery, John; Podust, Larissa M.; Li, Zhe; Furan, Lawrence R.; Yun-Fang Yang; Ramabhadran, Raghunath O.; Gilbert, Michael M. (August 2015). "Enzymatic hydroxylation of an unactivated methylene C–H bond guided by molecular dynamics simulations". Nature Chemistry. 7 (8): 653–660. Bibcode:2015NatCh...7..653N. doi:10.1038/nchem.2285. ISSN 1755-4349. PMC 4518477 . PMID 26201742.
