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Řádek 46:
 
== Řízená C-H aktivace ==
Pod řízenou C-H aktiivaci spadají postupy, které využívají [[řídicí skupina|řídicí skupiny]] ovlivňující regiochemii a stereochemii.<ref>{{Citace periodika | autor1 = T. Brückl | autor2 = R. D. Baxter | autor3 = Y. Ishihara | autor4 = P. S. Baran | titul = Innate and Guided C-H Functionalization Logic | periodikum = Accounts of Chemical Research | rok vydání = 2012 | strany = 826–839 | doi = 10.1021/ar200194b | pmid = 22017496}}</ref>
<!-- Directed-, chelation-assisted-, or "guided" C-H activation involves [[directing group]]s that influence regio- and stereochemistry.<ref name="Bruckl">{{cite journal | title = Innate and Guided C-H Functionalization Logic | journal = Accounts of Chemical Research | year = 2012 | volume = 45 | issue = 6 | pages = 826–839 | last1 = Brückl | first1 = T. | last2 = Baxter | first2 = R. D. | last3 = Ishihara | first3 = Y. | last4 = Baran | first4 = P. S. | author-link4 = Phil S. Baran | doi = 10.1021/ar200194b| pmid = 22017496 | pmc = 3288638 }}</ref> This is the most useful style of C-H activation in organic synthesis. [[N,N-dimethylbenzylamine]] undergoes [[cyclometalation]] readily by many transition metals.<ref>{{cite journal | last1 = Chetcuti | first1 = Michael J. | last2 = Ritleng | first2 = Vincent | year = 2007 | title = Formation of a Ruthenium–Arene Complex, Cyclometallation with a Substituted Benzylamine, and Insertion of an Alkyne | journal = J. Chem. Educ. | volume = 84 | issue = 6| page = 1014 | doi=10.1021/ed084p1014| bibcode = 2007JChEd..84.1014C }}</ref> A semi-practical implementations involve weakly coordinating directing groups, as illustrated by the [[Murai reaction]].<ref>{{cite journal|last=Murai|first=Shinji|author2=Kakiuchi, Fumitoshi |author3=Sekine, Shinya |author4=Tanaka, Yasuo |author5=Kamatani, Asayuki |author6=Sonoda, Motohiro |author7= Chatani, Naoto |title=Efficient catalytic addition of aromatic carbon–hydrogen bonds to olefins|journal=Nature|year=1993|volume=366|issue=6455|pages=529–531|doi=10.1038/366529a0|bibcode = 1993Natur.366..529M}}</ref>
 
Tento postup je nejúčinnějším známým postupem aktivace vazeb C-H. [[N,N-dimethylbenzylamin|''N'',''N''-dimethylbenzylamin]] může být snadno [[metalocyklické sloučeniny|cyklometalován]] řadou přechodných kovů.<ref>{{Citace periodika | autor1 = Michael J. Chetcuti | autor2 = Vincent Ritleng | titul = Formation of a Ruthenium–Arene Complex, Cyclometallation with a Substituted Benzylamine, and Insertion of an Alkyne | periodikum = Journal of Chemical Education | rok vydání = 2007 | strany = 1014 | doi = 10.1021/ed084p1014 | bibcode = 2007JChEd..84.1014C}}</ref>
[[File:Figure_1._General_scheme_of_a_Murai_reaction.png|center|thumb|504x504px|Murai reaction. X = [[directing group]].]]▼
 
Bylo zavedeno několik úprav, jako je například použití [[nekoordinující anion|slabě koordinujících]] skupin v&nbsp;[[Muraiova reakce|Muraiově reakci]].<ref>{{Citace periodika | autor1 = Shinji Murai | autor2 = Fumitoshi Kakiuchi | autor3 = Shinya Sekine | autor4 = Yasuo Tanaka | autor5 = Asayuki Kamatani | autor6 = Motohiro Sonoda | autor7 = Naoto Chatani | titul = Efficient catalytic addition of aromatic carbon–hydrogen bonds to olefins | periodikum = [[Nature]] | rok vydání = 1993 | strany = 529–531 | doi = 10.1038/366529a0 | bibcode = 1993Natur.366..529M}}</ref>
The mechanism for the Pd-catalyzed C-H activation reactions of [[2-Phenylpyridine|2-phenylpyridine]] involves a metallacycle intermediate. The intermediate is oxidized to form a Pd<sup>IV</sup> species, followed by reductive elimination to form the C-O bond and release the product.<ref>{{cite journal | last1 = Lyons | first1 = T. W. | last2 = Sanford | first2 = M. S. | year = 2010 | title = Palladium-Catalyzed Ligand-Directed C–H Functionalization Reactions | journal = Chem. Rev. | volume = 110 | issue = 2| pages = 1147–1169 | doi = 10.1021/cr900184e | pmid = 20078038 | pmc = 2836499 }}</ref>
[[File:Sanford Figure 2 mechanism.png|350px|right|thumb|Mechanism for Pd-catalyzed C-H activation.]]▼
 
▲[[FileSoubor:Figure_1._General_scheme_of_a_Murai_reaction.png|center|thumb|504x504px500x500px|MuraiMuraiova reaction.reakce; X =je [[directingřídicí group]]skupina.]]
===Borylation===
Transforming C-H bonds into C-B bonds through [[borylation]] has been thoroughly investigated due to their utility in synthesis (i.e. for cross-coupling reactions). [[John F. Hartwig|J. F. Hartwig]] reported a highly regioselective arene and alkane borylation catalyzed by a rhodium complex. In the case of alkanes, exclusive terminal functionalization was observed.<ref>{{cite journal | last1 = Chen | first1 = Huiyuan | last2 = Schlecht | first2 = Sabine | last3 = Semple | first3 = Thomas C. | last4 = Hartwig | first4 = John F. | year = 2000 | title = Thermal, Catalytic, Regiospecific Functionalization of Alkanes | journal = Science | volume = 287 | issue = 5460| pages = 1995–1997 | doi = 10.1126/science.287.5460.1995 | pmid = 10720320 | bibcode = 2000Sci...287.1995C }}</ref>
 
Mechanismus C-H aktivace [[2-fenylpyridin]]u kazalyzované paladiem zahrnuje metalocyklický meziprodukt. Tento meziprodukt se oxiduje na paladičitou sloučeninu, u níž poté proběhne [[redukční eliminace]] vazby C-O a vytvoří se konečný produkt.<ref>{{Citace periodika | autor1 = T. W. Lyons | autor2 = M. S. Sanford | titul = Palladium-Catalyzed Ligand-Directed C–H Functionalization Reactions | periodikum = [[Chemical Reviews]] | rok vydání = 2010 | strany = 1147–1169 | doi = 10.1021/cr900184e | pmid = 20078038}}</ref>
[[File:Hartwig figure 1 borylation.png|500px|center|Hartwig borylation]]▼
 
▲[[FileSoubor:Sanford Figure 2 mechanism.png|350px|right|thumb|MechanismMechanismus foraktivace Pd-catalyzedvazby C-H activation.katalyzované paladiem]]
Later, ruthenium catalysts were discovered to have higher activity and functional group compatibility.<ref>{{cite journal | title = Ruthenium-Catalyzed Regiospecific Borylation of Methyl C-H bonds | journal = J. Am. Chem. Soc. | year = 2006 | volume = 128 | issue = 42 | pages = 13684–13685 | last1 = Murphy | first1 = J. M. | last2 = Lawrence | first2 = J. D. | last3 = Kawamura | first3 = K. | last4 = Incarvito | first4 = C. | last5 = Hartwig | first5 = J. F. | doi = 10.1021/ja064092p | pmid=17044685}}</ref>
 
=== Borylace ===
[[File:Ru cat. borylation.png|300px|center|Ru catalyst based borylation]]▼
Přeměna vazeb C-H na vazby C-B skrze [[borylace|borylační reakce]] byla díky své syntetické využitelnosti prozkoumána podrobně. [[John F. Hartwig]] popsal vysoce regioselektivní borylace alkanů a arenů katalyzované komplexy rhodiua. U alkanů docházelo výhradně ke koncové funkcionalizaci.<ref>{{Citace periodika | autor1 = Huiyuan Chen | autor2 = Sabine Schlecht | autor3 = Thomas C. Semple | autor4 = John F. Hartwig | titul = Thermal, Catalytic, Regiospecific Functionalization of Alkanes | periodikum = [[Science]] | rok vydání = 2000 | strany = 1995–1997 | doi = 10.1126/science.287.5460.1995 | pmid = 10720320 | bibcode = 2000Sci...287.1995C}}</ref>
 
▲[[FileSoubor:Hartwig figure 1 borylation.png|500px|center|HartwigHartwigova borylationborylace]]
Other borylation catalysts have also been developed, including iridium-based catalysts, which successfully activate C-H bonds with high compatibility.<ref>{{cite journal | title = Mild Iridium-Catalyzed Borylation of Arenes. High Turnover Numbers, Room Temperature Reactions, and Isolation of a Potential Intermediate | journal = J. Am. Chem. Soc. | year = 2002 | volume = 124 | issue = 3 | pages = 390–391 | last1 = Ishiyama | first1 = T. | last2 = Takagi | first2 = J. | last3 = Ishida | first3 = K. | last4 = Miyaura | first4 = N. | last5 = Anastasi | first5 = N. R. | last6 = Hartwig | first6 = J. F. | doi = 10.1021/ja0173019| pmid = 11792205 }}</ref><ref>{{cite journal | title = A Stoichiometric Aromatic C-H Borylation Catalyzed by Iridium(I)/2,2′-Bipyridine Complexes at Room Temperature | journal = Angewandte Chemie International Edition | year = 2002 | volume = 41 | issue = 16 | pages = 3056–3058 | last1 = Ishiyama | first1 = T. | last2 = Takagi | first2 = J. | last3 = Hartwig | first3 = J. F. | last4 = Miyaura | first4 = N. | doi=10.1002/1521-3773(20020816)41:16<3056::aid-anie3056>3.0.co;2-#}}</ref><ref>{{cite journal | title = High-Turnover Aromatic C–H Borylation Catalyzed by POCOP-Type Pincer Complexes of Iridium | journal = J. Am. Chem. Soc. | year = 2016 | volume = 138 | issue = 30 | pages = 9487–9497 | last1 = Press | first1 = L. P. | last2 = Kosanovich | first2 = A. J. | last3 = McCulloch | first3 = B. J. | last4 = Ozerov | first4 = O. V. | doi = 10.1021/jacs.6b03656| pmid = 27327895 }}</ref>
 
PÚozději bylo zjištěno, že použitím katalyzátorů založených na rutheniu lze dosáhnout vyšší aktivity a kompatibility funkčních skupin.<ref>{{Citace periodika | autor1 = J. M. Murphy | autor2 = J. D. Lawrence | autor3 = K. Kawamura | autor4 = C. Incarvito | autor5 = J. F. Hartwig | titul = Ruthenium-Catalyzed Regiospecific Borylation of Methyl C-H bonds | periodikum = [[Journal of the American Chemical Society]] | rok vydání = 2006 | strany = 13684–13685 | doi = 10.1021/ja064092p | pmid = 17044685}}</ref>
For more information, consult [[borylation]].
 
▲[[FileSoubor:Ru cat. borylation.png|300px|center|RuBorylace catalystpomocí basedrutheniového borylationkatalyzátoru]]
 
Byly vyvinuty i jiné katalyzátory borylací, například založené na iridiu, dobře využitelné pro aktivace vazeb C-H.<ref>{{Citace periodika | autor1 = T. Ishiyama | autor2 = J. Takagi | autor3 = K. Ishida | autor4 = N. Miyaura | autor5 = N. R. Anastasi | autor6 = J. F. Hartwig | titul = Mild Iridium-Catalyzed Borylation of Arenes. High Turnover Numbers, Room Temperature Reactions, and Isolation of a Potential Intermediate | periodikum = Journal of the American Chemical Society | rok vydání = 2002 | strany = 390–391 | doi = 10.1021/ja0173019 | pmid = 11792205}}</ref><ref>{{Citace periodika | autor1 = T. Ishiyama | autor2 = J. Takagi | autor3 = J. F. Hartwig | autor4 = N. Miyaura | titul = A Stoichiometric Aromatic C-H Borylation Catalyzed by Iridium(I)/2,2′-Bipyridine Complexes at Room Temperature | periodikum = [[Angewandte Chemie|Angewandte Chemie International Edition]] | rok vydání = 2002 | strany = 3056–3058 | doi = 10.1002/1521-3773(20020816)41:16<3056::aid-anie3056>3.0.co;2-#}}</ref><ref>{{Citace periodika | autor1 = L. P. Press | autor2 = A. J. Kosanovich | autor3 = B. J. McCulloch | autor4 = O. V. Ozerov | titul = High-Turnover Aromatic C–H Borylation Catalyzed by POCOP-Type Pincer Complexes of Iridium | periodikum = Journal of the American Chemical Society | rok vydání = 2016 | strany = 9487–9497 | doi = 10.1021/jacs.6b03656 | pmid = 27327895}}</ref>
 
<!-- ==Natural gas==▼
 
▲==Natural gas==
{{Main|Methane functionalization}}
[[Natural gas|Naturally occurring]] [[methane]] is not utilized as a chemical feedstock, despite its abundance and low cost. Current technology makes prodigious use of methane by steam reforming to produce [[syngas]], a mixture of carbon monoxide and hydrogen. This syngas is then used in Fischer-Tropsch reactions to make longer carbon chain products or methanol, one of the most important industrial chemical feedstocks.<ref>{{cite book |last=Sen |first=A. |editor-last=Murai |editor-first=S. |title=Activation of Unreactive Bonds and Organic Synthesis |publisher=Springer Berlin Heidelberg |date=1999 |volume=3 |pages=81–95 |chapter=Catalytic Activation of Methane and Ethane by Metal Compounds |isbn=978-3-540-64862-8}}</ref><ref>{{Cite web|title = Methanol|url = http://www.essentialchemicalindustry.org/chemicals/methanol.html|website = www.essentialchemicalindustry.org|access-date = 2016-02-01}}</ref> An intriguing method to convert these hydrocarbons involves C-H activation. [[Roy A. Periana|Periana]], for example, reported that complexes containing late transition metals, such as [[Platinum|Pt]], [[Palladium|Pd]], [[Gold|Au]], and [[Mercury (element)|Hg]], react with [[methane]] (CH<sub>4</sub>) in H<sub>2</sub>SO<sub>4</sub> to yield [[methyl bisulfate]].<ref>{{cite journal | title = A Mercury-Catalyzed, High-Yield System for the Oxidation of Methane to Methanol | journal = Science| year = 1993| volume =259 | issue = 5093| pages= 340–343 | last1 = Periana| first1 = R.A. | last2 = Taube | first2 = D.J. | last3 = Evitt | first3 = E.R. | pmid = 17832346 | last4 = Loffler| first4 = D.G. | last5 = Wentrcek | first5 = P.R. | last6 = Voss | first6 =G. | last7 =Masuda | first7 = T. | doi = 10.1126/science.259.5093.340| bibcode = 1993Sci...259..340P}}</ref><ref name="Natural">{{cite journal | title = Platinum Catalysts for the High-Yield Oxidation of Methane to a Methanol Derivative | journal = Science | year = 1998 | volume = 280 | pages = 560–564 | last1 = Periana | first1 = R. A. | last2 = Taube | first2 = D. J. | last3 = Gamble | first3 = S. | last4 = Taube | first4 = H. | last5 = Satoh | first5 = T. | last6 = Fujii | first6 = H. | doi = 10.1126/science.280.5363.560 | pmid = 9554841 | issue = 5363|bibcode = 1998Sci...280..560P }}</ref> The process has not however been implemented commercially.
 
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