Substitutionsreaktionen mit metallorganischen Verbindungen, IV. Mitteil.: Die Grignardierung methoxylhaltiger aromatischer Nitrile

Richtzenhain, Hermann; Nippus, Peter

doi:10.1002/cber.19490820417

Cited by 14 publications

(5 citation statements)

References 12 publications

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“…2,3-Dimethoxybenzophenone. Yield: 1.5 g (63%), colorless oil. 1 H NMR (CDCl 3 , 400 MHz): δ (ppm) = 7.83 (m, 2 H), 7.55 (m, 1 H), 7.43 (m, 2 H), 7.12 (t, J = 7.7 Hz, 1 H), 7.05 (dd, J = 7.7, 1.6 Hz, 1 H), 6.92 (dd, J = 7.7, 1.6 Hz, 1 H), 3.90 (s, 3 H), 3.71 (s, 3 H).…”

Section: Methodsmentioning

confidence: 99%

Hierarchical Assembly of Helicate-Type Dinuclear Titanium(IV) Complexes

et al. 2005

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The ligands 4-7-H(2) were used in coordination studies with titanium(IV) and gallium(III) ions to obtain dimeric complexes Li(4)[(4-7)(6)Ti(2)] and Li(6)[(4/5a)(6)Ga(2)]. The X-ray crystal structures of Li(4)[(4)(6)Ti(2)], Li(4)[(5b)(6)Ti(2)], and Li(4)[(7a)(6)Ti(2)] could be obtained. While these complexes are triply lithium-bridged dimers in the solid state, a monomer/dimer equilibrium is observed in solution by NMR spectroscopy and ESI FT-ICR MS. The stability of the dimer is enhanced by high negative charges (Ti(IV) versus Ga(III)) of the monomers, when the carbonyl units are good donors (aldehydes versus ketones and esters), when the solvent does not efficiently solvate the bridging lithium ions (DMSO versus acetone), and when sterical hindrance is minimized (methyl versus primary and secondary carbon substituents). The dimer is thermodynamically favored by enthalpy as well as entropy. ESI FT-ICR mass spectrometry provides detailed insight into the mechanisms with which monomeric triscatecholate complexes as well as single catechol ligands exchange in the dimers. Tandem mass spectrometric experiments in the gas phase show the dimers to decompose either in a symmetric (Ti) or in an unsymmetric (Ga) fashion when collisionally activated. The differences between the Ti and Ga complexes can be attributed to different electronic properties and a charge-controlled reactivity of the ions in the gas phase. The complexes represent an excellent example for hierarchical self-assembly, in which two different noncovalent interactions of well balanced strengths bring together eleven individual components into one well-defined aggregate.

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Section: Methodsmentioning

confidence: 99%

Hierarchical Assembly of Helicate-Type Dinuclear Titanium(IV) Complexes

et al. 2005

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“…Most other Grignard reagents react similarly, but the methyl Grignard reagent prefers to add to the cyano group, giving 2,3-dimethoxyacetophenone and some o-hydroxy ketone (3,17). Attempts (201,480) to extend this reaction to other methoxybenzonitriles have for the most part not been successful. Similar replacement of methoxy groups is observed in the treatment of certain hindered aromatic ketones with Grignard reagents, as in the formation of mesityl 2-methyl-1 -naphthyl ketone (II) from the action of methylmagnesium bromide on mesityl 2-methoxy-1 -naphthyl ketone (I) (202).…”

Section: E Replacement Of Sulfonate and Other Ester Groupsmentioning

confidence: 99%

Aromatic Nucleophilic Substitution Reactions.

Bunnett¹,

Zahler²

1951

Chem. Rev.

1,035

500

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“…However, the reaction was lower yielding for Grignard reagents and nearly failed for tert -butyl lithium (Scheme 3, i ). 9 In the 1970’s Myers explored using an aryl oxazoline as a surrogate to the earlier nitrile system (Scheme 3 , ii .) The reaction proved very useful for less congested aliphatic and aryl nucleophiles.…”

Section: Ipso -S N Ar Reactions Of Aryl Metho...mentioning

confidence: 99%

Strategies for ortho-tert-Butylation of Phenols and their Analogues

Pettus¹,

Chan²

2022

Synlett

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A new general process for constructing ortho-tert-butyl phenols is presented within the context of other known methods. All are briefly evaluated with regards to regioselectivity, efficiency, and functional group tolerance. In addition, we present an assortment of tert-butyl substrates accessed through o-QM chemistry. Our conclusion is that the o-QM process provides greater yields, flexibility, and generality than most other known methods for delivering ortho-tert-buytlated phenols and their derivatives.1 Introduction2 Friedel–Crafts Alkylation3 Addition of t-Bu– or t-Bu• to Carbonyl Compounds4 ipso-SNAr Reactions of Aryl Methoxy and tert-Butylsulfoxide Moieties5 Metal-Mediated Coupling of Aryl Bromides6 Applications of o-Quinone Methides (o-QMs)7 Conclusion

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Substitutionsreaktionen mit metallorganischen Verbindungen, IV. Mitteil.: Die Grignardierung methoxylhaltiger aromatischer Nitrile

Abstract: Es werden mehrere methoxylhaltige Nitrile der Benzol‐ und Naphthalinreihe dargestellt und mit Grignard‐Verbindungen umgesetzt, um den Einfluß von Substituenten auf den Austausch von Methoxygruppen gegen Alkyl‐ oder Arylreste von Grignard‐Verbindungen zu prüfen.

Cited by 14 publications

References 12 publications

Hierarchical Assembly of Helicate-Type Dinuclear Titanium(IV) Complexes

Hierarchical Assembly of Helicate-Type Dinuclear Titanium(IV) Complexes

Aromatic Nucleophilic Substitution Reactions.

Strategies for ortho-tert-Butylation of Phenols and their Analogues

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