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Showing 1 to 13 of 13 for “"Directed Ortho Metalation"”.
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Directed Ortho-Metalation of Dimethylarylamines
… electrophilic aromatic substitution (EAS) or directed ortho-metalation (DoM). Directed ortho-metalation (DoM) is an alternative aromatic substitution process initiated by organolithium reagents which provides regiospecific substitution exclusively at the ortho- position (equation). The focus …
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Directed ortho Metalation in Hydrocarbon Solvents: Opposing Pi-Resonance Effects
… reagents and do not typically support ortho-metalation reactions without the aid of a promoter. An exception would be an arene substrate having the capability to bidentate complex to the reactive alkyllithium dimer, which enables ortho-metalation to occur in high yields. A second, more …
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Directed Ortho-Metalation of the Three Methyl Anisoles in Various Media
Directed ortho-metalation (DoM) is a very useful alternative to electrophillic aromatic substitution (EAS) for the synthesis of substituted aromatic compounds. DoM is highly regiospecific providing metalation chiefly in the ortho-position. However, lateral (a-) metalation of an alkyl side-chain and …
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Advances in the synthesis of indazoles: regioselective C-7 functionalization by directed ortho metalation and progress towards indazole based azaborine compounds
… incorporating the indazole framework using Directed ortho Metalation (DoM) reactions as a key step, as well as devise new methods for C-7 functionalization of indazole heterocycles using DoM reactions. Successful N-1 functionalization of indazoles enabled the subsequent Suzuki-Miyaura or …
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ADVANCES IN THE DIRECTED ORTHO METALATION, SUZUKI-MIYAURA CROSS COUPLING, AND RING-OPENING REACTIONS OF INDAZOLES. SYNTHESIS OF LUMINESCENT ACRIDINE AND NOVEL INDAZOLE-BASED OXAZABORINES
The Directed ortho Metalation (DoM) reaction is a ubiquitous tool in the synthesis of polyfunctionalized aromatic and heteroaromatic molecules. Its regioselective nature endowed by the virtue of directed metalation groups (DMGs) coupled with its compatibility alongside many other well-established …
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Metalation of the Di- and Tri-Methoxybenzenes
… reagents and also to afford little support for ortho-metalation reactions. In contrast, both m- and odimethoxybenzene afford 80% "ion-multiple specific" monometalation in hydrocarbon solvent (n-hexane, cyclohexane, toluene) without the addition of any catalyst (ether or amine). These …
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2,3-Dihalofenoles: sustratos de partida versátiles para la síntesis de heterociclos funcionalizados regioselectivamente
… benzo[b]furans and benzo[b]thiophenes. The directed ortho-metalation strategy in conjunction with palladium-catalyzed cross-coupling reactions have been mainly used to achieve this goal. The potential of these synthetic routes is that they allow an easy access to a wide variety of …
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New synthetic approaches to 8,5'-neolignans
… Synthesis of several new phosphorous-based directed ortho-metalation groups was studied. The examined compounds having these new groups decomposed even under very mild reaction conditions and are not suitable for the application in the synthesis. The second strategy was to examine one [3+2] …
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New lithium cuprates for the promotion of directed organic transformations
… stereoselective organic transformations via Directed ortho Metalation (DoM) is an important synthetic tool and requires thorough investigation to maximise efficiency and develop a mechanistic understanding. This thesis begins with a discussion of the history of DoM covering firstly …
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Synthetic Studies Towards the Crisamicins
This thesis describes synthetic work directed towards the synthesis of the dimeric pyranonaphthoquinone antibiotic crisamicin A 1.46 and its regioisomer 2.77. The synthetic strategy adopted is based on a double furofuran annulation/oxidative rearrangement strategy that has been successfully used by …
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Reinventing Aromatic Substitution: A Novel Look
<p>Electrophilic aromatic substitution (EAS) and directed <em>ortho</em>-metalation (DoM) involve the direct substitution of an arene hydrogen. A major drawback involving EAS is the necessity for harsh forcing conditions for the reaction to proceed. Catalysts such as Lewis acids FeBr<sub>3</sub> …
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Group 11 'Ate Bases: Towards an Understanding of Solid- and Solution-State Structures
… metalate aromatic compounds, via directed ortho cupration (DoCu). This thesis begins with an introduction to aspects of the chemistry of organolithium compounds, group 11 organometallic compounds and their lithium 'ate complexes. Examples of such synergic bases are presented and …
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A Convenient Synthesis of Pyrrolnitrin and Related Halogenated Phenylpyrroles
This thesis details a straightforward synthetic route to the antifungal compound pyrrolnitrin 1.2, along with several analogous halogenated phenylpyrroles. The proposed synthetic protocol involved the Suzuki-Miyaura cross-coupling of appropriately halogenated pyrrole pinacolboronate esters and aryl …