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- ...[[carbocation]]s achieve additional stabilization. Consequently, true 1° carbocations (with a classical structure) may be rare or nonexistent.{{cln|What on this [[Category:Carbocations]] ...3 Кб (444 слова) - 20:47, 4 марта 2024
- ...er bound penta- or tetracoordinated (nonclassical) carbonium ions. Role of carbocations in electrophilic reactions|authorlink=George A. Olah|last=Olah|first=G. A.| [[Category:Carbocations]] ...5 Кб (633 слова) - 12:39, 2 февраля 2024
- ...er bound penta- or tetracoordinated (nonclassical) carbonium ions. Role of carbocations in electrophilic reactions | author = George Andrew Olah | author-link = Ge [[Category:Carbocations]] ...6 Кб (728 слов) - 01:24, 15 февраля 2024
- ...er bound penta- of tetracoordinated (nonclassical) carbonium ions. Role of carbocations in electrophilic reactions" [[George Andrew Olah]]; ''J. Am. Chem. Soc.''; ...carbocations, because they are stabilized by [[hyperconjugation]]. Primary carbocations are highly unstable. Therefore, reactions such as the [[SN1 reaction|S<sub> ...12 Кб (1676 слов) - 01:04, 15 февраля 2024
- ...od donors in hyperconjugation resulting in a considerable stabilization of carbocations. In contrast to double bonds, stabilization of radicals is weaker and stabi ...2 Кб (301 слово) - 12:39, 23 февраля 2024
- ....org/nobel_prizes/chemistry/laureates/1994/olah-lecture.html My Search for Carbocations and Their Role in Chemistry] Nobel Lecture, December 8, 1994, by George A. ...with another Hungarian chemist, Stephen J. Kuhn. Olah's pioneering work on carbocations started during his eight years with Dow.<ref>{{cite book | author = George ...17 Кб (2155 слов) - 07:13, 12 марта 2024
- * V.G.Shubin and G.I. Borodkin. Long-Lived Carbocations in Cold Siberia. Chapter 6, pp. 125—158 Carbocation Chemistry (collective ...5 Кб (67 слов) - 16:00, 1 октября 2023
- ...ast3=Mateescu|first3=G. D.|last4=Riemenschneider|first4=J. L.|title=Stable Carbocations. CL. Fourier Transform 13C Nuclear Magnetic Resonance and X-ray Photoelectr ...lassical model, (b) describes a rapid equilibration between three distinct carbocations rather than delocalization. In 1973 Olah confirmed the validity of the non- ...20 Кб (2818 слов) - 23:37, 23 марта 2024
- [[Category:Carbocations]] ...4 Кб (433 слова) - 19:09, 2 февраля 2024
- ...r HP, Moran MD, Schrobilgen GJ, Steinberg C, Suontamo RJ. The syntheses of carbocations by use of the noble-gas oxidant, {{chem|[XeOTeF|5|][Sb(OTeF|5|)|6|]}}: the ...8 Кб (1175 слов) - 05:12, 26 марта 2024
- 4 Кб (546 слов) - 04:14, 20 февраля 2024
- ...5|+}} and [[Vinyl cation|vinyl]] {{chem|C|2|H|3|+}} cations. Occasionally, carbocations that bear more than one positively charged carbon atom are also encountered ...{{chem|CR|5|+}}, where R is H or alkyl), to the exclusion of non-classical carbocations like the [[ Norbornyl cation |2-norbornyl cation]].<ref>{{Cite journal|last ...42 Кб (6040 слов) - 01:07, 15 февраля 2024
- ...[[rearrangement reaction]]s are rare compared to rearrangements involving carbocations and restricted to [[aryl]] migrations. ...6 Кб (702 слова) - 01:38, 10 марта 2024
- ...cleavage. However, reactions that would require the formation of unstable carbocations ([[methyl]], [[Vinyl group|vinyl]], [[aryl]] or [[primary carbon]]) proceed ...6 Кб (763 слова) - 20:50, 4 марта 2024
- 6 Кб (772 слова) - 13:43, 9 марта 2024
- [[Category:Carbocations]] ...6 Кб (807 слов) - 20:32, 4 марта 2024
- ...almost an order of magnitude weaker than the case of alkyl substitution on carbocations (σ<sub>C–H</sub>→p<sub>C</sub>), since an unfilled p orbital is lower ...20 Кб (2751 слово) - 01:33, 24 марта 2024
- ...structures differing only minutely in energy. Certainly, not all bicyclic carbocations are non-classical; the energy difference between classical and non-classica ...surprising as primary [[carbocation]]s are much less stable than secondary carbocations. However, the 2-norbornyl cation can be formed from derivatives of β-(Δ{{ ...50 Кб (6913 слов) - 13:52, 21 декабря 2023
- ...e direction of [[George Olah]], where he worked on characterizing stable [[carbocations]] in superacids.<ref name=":0">{{Cite web|url=http://chem.usc.edu/faculty/P ...7 Кб (852 слова) - 20:42, 10 марта 2024
- 7 Кб (928 слов) - 15:56, 11 февраля 2024