Unreferenced stub auto yes date December 2009 Metalation metallation is a chemical reaction which results in a metal atom being attached to a usually Organic compound organic molecule. Lithium metal in contact with an organohalide lithiates the organic molecule and gives the organolithium reagent and lithium halide. Magnesium similarly metalates organohalides to give Grignard reagent s. Protons on a molecule that are acidic, even only slightly, can be exchanged for a metal by a suitable butyllithium reagent mixture. Transmetalation is the exchange of two metals between organic molecules. For example, transmetalations can be accomplished by reacting an organolithium reagent with a metal salt. Category Organometallic chemistry Reaction stub es Metalaci n nl Metallatie ... more details
Directed ortho metalation DoM is an adaptation of electrophilic aromatic substitution in which electrophile s attach themselves exclusively to the ortho position of a direct metalation group or DMG through the intermediary of an aryllithium compound ref Directed ortho metalation. Tertiary amide and O carbamate directors in synthetic strategies for polysubstituted aromatics Victor Snieckus Chem. Rev. 1990 90 6 879 933. http pubs.acs.org cgi bin abstract.cgi chreay 1990 90 i06 f pdf f cr00104a001.pdf Abstract ref . The DMG interacts with lithium through a hetero atom . Examples of DMG s are the methoxy group, a tertiary amine group and an amide group. Image Directedorthometalation.png 600px center Scheme 1. Directed ortho metalation The general principle is outlined in scheme 1 . An aromatic ring system with a DMG group 1 interacts with an alkyllithium such as N Butyllithium n butyllithium in its specific aggregation state hence R Li sub n sub to intermediate 2 since the hetero atom on the DMG is a Lewis base and lithium the Lewis acid . The very basic alkyllithium then deprotonation deprotonates the ring in the nearest ortho position forming the aryllithium 3 all the while maintaining the acid base interaction. An electrophile reacts in the next phase in an electrophilic aromatic substitution with a strong preference for the lithium Ipso substitution ipso position replacing the lithium ... Compounds. XX. Metalation Henry Gilman , Robert L. Bebb J. Am. Chem. Soc. 1939 61 1 109 112. http ... Metalation of Enantiopure Aromatic Sulfoxides and Stereocontrolled Addition to Imines Nicolas Le Fur ... ortho Metalation Boronation and Suzuki Miyaura Cross Coupling of Pyridine Derivatives A One Pot ... ortho Metalation Boronation and Suzuki Miyaura Cross Coupling of Pyridine Derivatives DOM has also ... preference. In one study ref Directed meta Metalation Using Alkali Metal Mediated Zincation David R ... References reflist DEFAULTSORT Directed Ortho Metalation Category Substitution reactions de Ortho ... more details
The Smiles rearrangement is an organic reaction and a rearrangement reaction . ref Truce, W. E. Kreider, E. M. Brand, W. W. Organic Reactions Org. React. 1970 , 18 . ref ref A. A. Levy, H. C. Rains and S. Smiles, J. Chem. Soc. 1931 , 3264. ref It is an intramolecular nucleophilic aromatic substitution of the type Image Smiles rearrangement.png center 400px Smiles rearrangement where X in the arene compound can be a sulfone , a sulfide , an ether or any substituent capable of dislodging from the arene carrying a negative charge. The terminal functional group in the chain end Y is able to act as a strong nucleophile for instance an alcohol , amine or thiol . As in other nucleophilic aromatic substitution s the arene requires activation by an electron withdrawing group preferably in the aromatic ortho position . In one modification called the Truce Smiles rearrangement the incoming nucleophile is sufficiently strong that the arene does not require this additional activation, for example when the nucleophile is an organolithium . This reaction is exemplified by the conversion of an aryl sulfone into an sulfinic acid by action of N Butyllithium n butyllithium ref Rearrangements of Aryl Sulfones. I. The Metalation and Rearrangement of Mesityl Phenyl Sulfone William E. Truce, William J. Ray, Oscar L. Norman, and Daniel B. Eickemeyer J. Am. Chem. Soc. 1958 80 14 pp 3625 3629 DOI 10.1021 ja01547a038 ref Image Truce Smiles rearrangement.png center 400px Truce Smiles rearrangement This particular reaction requires the interaction of the alkyllithium group ortho to the sulfone group akin a directed ortho metalation . A conceptually related reaction is the Chapman rearrangement . External links Appearance in Organic syntheses Org. Synth. 2007 , 84, 325 333 http www.orgsynth.org orgsyn pdfs V84P0325.pdf Article References references Category rearrangement reactions Category Name reactions de Smiles Umlagerung ja zh Smiles ... more details
wiktionary DOM DOM may refer to D.O.M. restaurant , a restaurant in S o Paulo, Brazil Days on market , how many days since a piece of real estate was listed for sale Deo optimo maximo , Latin for to the Greatest and Best God , originally Jove, later the Christian God Differential object marking , a linguistic phenomenon Directed ortho metalation , a chemical reaction mechanism Disk on module , an alternative to traditional computer hard disks Document Object Model , a way to refer to XML or X HTML elements as objects Dominican Republic ISO 3166 1 country code Dominion of Melchizedek DoM , a micronation known largely for facilitating large scale banking fraud in many parts of the world lang fr D partement d outre mer or overseas department, a French overseas d partement Melville Hall Airport s IATA code Drawn over mandrel, a Tubing material Manufacture class of manufactured tubing 2,5 Dimethoxy 4 methylamphetamine or DOM STP, a hallucinogenic phenethylamine See also Dom disambiguation disambiguation et DOM es DOM eo DOM fa DOM fr DOM it DOM la DOM lt DOM ja DOM no DOM sl DOM th DOM zh DOM ... more details
. A general, highly selective method for benzylic metalation using a mixed lithium and potassium metal amide LiNK chemistry has been developed which permits metalation regardless of the relative position ... metalation 2 none of the ortho lithiated product 3 is observed. This result is explained by a mechanism ... more details
Refimprove date December 2009 DISPLAYTITLE Di tert butylzinc Chembox verifiedrevid 334961503 Name Di tert butylzinc ImageFile Di tert butylzinc.png ImageSize 150px ImageFile1 Di tert butylzinc from xtal 3D balls B.png ImageSize1 170px IUPACName Bis dimethylethyl zinc OtherNames Di tert butylzinc Section1 Chembox Identifiers CASNo 16636 96 7 CASNo Ref cascite correct CAS PubChem SMILES Section2 Chembox Properties C 8 H 8 Zn 1 Appearance Density MeltingPt BoilingPt Solubility Section3 Chembox Hazards MainHazards FlashPt Autoignition Di tert butylzinc is a Chemical compound compound with the formula ZnC sub 8 sub H sub 18 sub . This compound is used as a meta activating reagent in the syntheses of Di tert butylzinc Related reaction N,N dimethyl 3 iodoaniline from Dimethylaniline N,N dimethylaniline . ref cite journal doi 10.1002 anie.200600720 title Directedmeta Metalation Using Alkali Metal Mediated Zincation year 2006 last1 Armstrong first1 David R. last2 Clegg first2 William last3 Dale first3 Sophie H. last4 Hevia first4 Eva last5 Hogg first5 Lorna M. last6 Honeyman first6 Gordon W. last7 Mulvey first7 Robert E. journal Angewandte Chemie International Edition volume 45 issue 23 pages 3775 ref References Reflist Zinc compounds DEFAULTSORT Di Tert Butylzinc Category Organozinc compounds Organic compound stub ... more details
. In collaboration with Peter Markov, Ivanov established for the first time the possibility for metalation ... reagents prepared by metalation of esters, nitriles and amides of alkanoic and arylacetic acids ... more details
compounds the metalation or Li H exchange reaction , with the exception of alkane s. In principle ... reaction theories base that is commercially available, with a pKa greater than 53. The metalation reaction ... , in situations where the lithium reagent but not the Grignard can be easily prepared by a metalation ... derivatives are intermediates in directed ortho metalation such as Me sub 2 sub NCH sub 2 ... more details
chembox verifiedrevid 414428222 ImageFile Ref chemboximage correct ?? ImageFile Benzyldimethylamine.svg ImageSize IUPACName N,N dimethyl 1 phenylmethanamine OtherNames N,N Dimethylbenzenemethanamine, N Benzyldimethylamine, Dimethylbenzylamine, Benzyl N,N dimethylamine, N Phenylmethyl dimethylamine, BDMA, Sumine 2015, Benzenemethanamine, Dabco B 16, Araldite accelerator 062, N,N Dimethyl phenyl methanamine Section1 Chembox Identifiers ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 7398 InChIKey XXBDWLFCJWSEKW UHFFFAOYAQ ChEMBL Ref ebicite correct EBI ChEMBL 45591 StdInChI Ref stdinchicite correct chemspider StdInChI 1S C9H13N c1 10 2 8 9 6 4 3 5 7 9 h3 7H,8H2,1 2H3 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey XXBDWLFCJWSEKW UHFFFAOYSA N CASNo Ref cascite correct CAS CASNo 103 83 3 EINECS 203 149 1 PubChem 7681 SMILES N C Cc1ccccc1 C InChI 1 C9H13N c1 10 2 8 9 6 4 3 5 7 9 h3 7H,8H2,1 2H3 Section2 Chembox Properties C 9 H 13 N 1 Appearance colourless to yellow liquid Density 0.91 g cm sup 3 sup at 20 C MeltingPt 75 C BoilingPt 180 183 C Solubility 1.2 g L 27 C Section3 Chembox Hazards MainHazards NFPA H 3 NFPA F 3 NFPA R 0 NFPA O RPhrases R10 , R20 , R21 , R22 , R34 , R52 , R53 SPhrases S26 , S36 , S45 , S61 FlashPt 55 C Autoignition 410 C Dimethylbenzylamine is the organic compound with the chemical formula formula C sub 6 sub H sub 5 sub CH sub 2 sub N CH sub 3 sub sub 2 sub . The molecule contains the benzyl group, C sub 6 sub H sub 5 sub CH sub 2 sub , attached to a dimethyl amino functional group . It is used as a catalyst for the formation of polyurethane foams and epoxy resins. Like some other benzyl compounds, the molecule undergoes directed ortho metalation with butyl lithium . Because of this reaction, many derivatives are known with the formula 2 X C sub 6 sub H sub 4 sub CH sub 2 sub N CH sub 3 sub sub 2 sub X SR, PR sub 2 sub , etc. . The amine is basic and undergoes quaternization with methyl iodide to give the ammonium sal ... more details
chembox verifiedrevid 446232164 ImageFile Xantphos.png ImageSize 170 ImageFile1 Xantphos 3D balls.png ImageSize1 220 IUPACName 4,5 Bis diphenylphosphino 9,9 dimethylxanthene OtherNames Xantphos Section1 Chembox Identifiers ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 551930 InChI 1 C39H32OP2 c1 39 2 33 25 15 27 35 41 29 17 7 3 8 18 29 30 19 9 4 10 20 30 37 33 40 38 34 39 26 16 28 36 38 42 31 21 11 5 12 22 31 32 23 13 6 14 24 32 h3 28H,1 2H3 InChIKey CXNIUSPIQKWYAI UHFFFAOYAQ StdInChI Ref stdinchicite correct chemspider StdInChI 1S C39H32OP2 c1 39 2 33 25 15 27 35 41 29 17 7 3 8 18 29 30 19 9 4 10 20 30 37 33 40 38 34 39 26 16 28 36 38 42 31 21 11 5 12 22 31 32 23 13 6 14 24 32 h3 28H,1 2H3 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey CXNIUSPIQKWYAI UHFFFAOYSA N CASNo Ref cascite correct ?? CASNo 161265 03 8 PubChem 636044 SMILES O6c1c cccc1P c2ccccc2 c3ccccc3 C c7cccc P c4ccccc4 c5ccccc5 c67 C C Section2 Chembox Properties Formula C sub 39 sub H sub 32 sub OP sub 2 sub MolarMass 578.62 g mol Appearance colorless solid Density 1.34 g mL MeltingPtCL 224 MeltingPtCH 228 BoilingPt Solubility organic solvents Section3 Chembox Hazards MainHazards flammable FlashPt Autoignition Xantphos is an organophosphorus compound derived from the heterocycle xanthene . It is used as a bidentate ligand and is noteworthy for having a particularly wide bite angle . Such ligands are useful in the hydroformylation of alkene s. ref cite journal author Piet W. N. M. van Leeuwen, Paul C. J. Kamer, Joost N. H. Reek, and Peter Dierkes title Ligand Bite Angle Effects in Metal catalyzed C C Bond Formation year 2000 journal Chemical Reviews volume 100 issue 8 pages 2741 2769 doi 10.1021 cr9902704 pmid 11749304 ref Illustrative of its wide bite angle, it forms both cis and trans adducts of platinum II chloride . A related bidentate ligand with a greater bite angle is spanphos . The ligand is prepared by double Directed ortho metalation directed lithiation of 9,9 di ... more details
, 85 , 2165. ref Metalation of terminal alkynes is a significant side reaction that occurs under these conditions. If metalation is desired, tertiary amine complexes of DIBAL H are useful. ref Binger ... of competitive metalation of terminal alkenes. The stereoselectivity of hydroalumination can be altered ... more details
use as a strong Base chemistry base is referred to as metalation . Reactions are typically conducted ... derivatives see below . Metalation main Organolithium reagent One of the most useful chemical properties ... 2.2.2 octane DABCO further polarize the Li C bond and accelerate the metalation. Such additives ... and is often used to accomplish difficult metalation s. The butoxide anion complexes the lithium ... more details
The Baker Venkataraman rearrangement is the chemical reaction of 2 acetoxyacetophenones with base to form 1,3 di ketone s. ref name baker1933 cite journal last Baker first W. journal Journal of the Chemical Society J. Chem. Soc. year 1933 pages 1381 1389 doi 10.1039 JR9330001381 title Molecular rearrangement of some o acyloxyacetophenones and the mechanism of the production of 3 acylchromones ref ref name venk1934 cite journal author Mahal, H. S. Venkataraman, K. journal Journal of the Chemical Society J. Chem. Soc. year 1934 pages 1767 1769 doi 10.1039 JR9340001767 title Synthetical experiments in the chromone. group. XIV. Action of sodamide on 1 acyloxy 2 acetonaphthones ref Image Baker Venkataraman Rearrangement Scheme.png center 400px The Baker Venkataraman rearrangement This rearrangement reaction proceeds via enolate formation followed by acyl transfer. It is named after the scientists Wilson Baker and Krishnasami Venkataraman. The Baker Venkataraman rearrangement is often used to synthesize chromone s and flavone s. ref name os1952 cite journal author T. S. Wheeler title Flavone journal Organic Syntheses url http www.orgsyn.org orgsyn prep.asp?prep cv4p0478 volume 32 pages 72 year 1952 also in the http www.orgsyn.org orgsyn pdfs cv4p0478.pdf Collective Volume 1963 4 478 PDF . ref ref cite journal last Jain first P. K. coauthors et al. journal Synthesis journal Synthesis year 1982 pages 221 222 doi 10.1055 s 1982 29755 title A Facile Baker Venkataraman Synthesis of Flavones using Phase Transfer Catalysis volume 1982 issue 03 ref ref cite journal author Kalinin, A. V. Da Silva, A. J. M. Lopes, C. C. Lopes, R. S. C. Snieckus, V. journal Tetrahedron Letters Tetrahedron Lett. date 9 July 1998 volume 39 issue 28 pages 4995 4998 doi 10.1016 S0040 4039 98 00977 0 title Directed ortho metalation cross coupling links. Carbamoyl rendition of the baker venkataraman rearrangement. Regiospecific route to substituted 4 hydroxycoumarins ref ref Kraus, G. A. Fulton, B. S. Woo ... more details
ref name seventeenth Direct metalation through C H activation C H bond activation ref name first ... of the carbene ligand to the metal center. Typically, direct metalation requires the blockage ..., as discussed earlier. Smaller substituents may be cleaved. Direct metalation by silver I with imidazolium ..., a silver carbene complex is produced by direct metalation. This silver complex is reacted via transmetalation ... more details
Orphan date July 2011 A tuck in complex is an organometallic molecule where a methyl group on a methyl substituted coordinated ring ligand bonds to the central metal. The term tuck in is coined from the fact that this reaction cause the ligand to bend back towards the metal as if it were being tucked in. During the process of tucking in, the methyl group loses a C H bond that is replaced with a C M bond. In cases where molecules undergo a tuck in , hydrogen gas often is produced. In many other tuck in reactions the ring methyl reacts displacing another methyl bound to the metal liberating methane. When first discovered a tuck in was thought to be a form of organic reaction called Directed ortho metalation ortho metallation . ref name Chem001Harder Harder, S. Intramolecular C H activation in alkaline earth metal complexes 42 Angew. Chem. Int. Ed. 2003 3430 3434. anie.200351055 ref They came to be known as cyclometallations instead because of the new metal containing ring that was formed in the process. This process readily happens at d sup 0 sup centers because it involves no intermediate where the metal uses non valence electrons. The most common cases of tucked in complexes involve a pentamethylcyclopentadienyl ring Cp . The reaction is not limited to Cp , as many other aromatic rings also share the same properties, such as benzene or cycloheptatriene , with methyl substitution. The first use of the term tucked in in the scientific literature was by Cloke et al. . ref name Chem001Geoffrey Cloke, G. N. Green, J. C. Green, M. H. and Morley, C. P. Metal Atom Synthesis and Photochemistry of Bis q pentamethylcyclopentadienyl tungsten Dihydride J. Chem. Soc, Chem. Communication 1985 3430 3434. doi 10.1039 C39850000945 ref Synthesis Forming a tucked in complex is a relatively simple reaction. Because it is an intramolecular reaction intramolecular rearrangement it requires no external chemicals or catalysts. With the addition of heat or light, an CH on a ring methyl i ... more details
TOCright Deoxyribozymes or DNA enzymes or catalytic DNA , or DNAzymes are deoxyribonucleic acid DNA molecules with catalyst catalytic action. In contrast to the RNA ribozyme that has many catalytic capabilities, DNA is only associated with gene DNA replication replication and nothing else. The reasons are that DNA lacks specific functional group s and that DNA prefers the double coil conformation in which potential catalytic sites are shielded. In comparison to protein s built up from 20 different monomer s both RNA and DNA have a much more restricted set of monomers 4 to choose from which limits the construction of interesting catalytic sites. For these reasons DNAzymes exist only in the laboratory. Discovery The first deoxyribozyme was discovered in 1994 ref cite journal journal Chem Biol. year 1994 month December volume 1 issue 4 pages 223 9 title A DNA enzyme that cleaves RNA author Breaker RR, coauthors Joyce GF. pmid 9383394 doi 10.1016 1074 5521 94 90014 0 ref by current Yale Professor Ronald R. Breaker while a postdoctoral fellow in the laboratory of Prof. Gerald Joyce at The Scripps Research Institute in La Jolla, CA. This deoxyribozyme assists in lead ion dependent RNA cleaving operations. Catalytic amplification was found to be 100 fold compared to the uncatalysed reaction. Many other deoxyribozymes have since been developed that catalyse DNA phosphorylation, DNA adenylation , DNA deglycosylation , porphyrin metalation , thymine dimer photoreversion and DNA cleavage. Of particular interest are DNA ligase s. ref cite journal title Deoxyribozymes DNA catalysts for bioorganic chemistry author Scott K. Silverman journal Org. Biomol. Chem. year 2004 volume 2 pages 2701 06 url http www.scs.uiuc.edu scott SilvermanPub30.pdf format PDF doi 10.1039 B411910J pmid 15455136 issue 19 ref These molecules have demonstrated remarkable chemoselectivity in RNA branching reactions. Although each repeating unit in a RNA strand owns a free hydroxyl group, the DNA ligase takes ... more details
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