Alkali‐Metal‐Mediated Zincation of Ferrocene: Synthesis, Structure, and Reactivity of a Lithium Tmp/Zincate Reagent

Barley, Helen R. L.; Clegg, William; Dale, Sophie H.; Hevia, Eva; Honeyman, Gordon W.; Kennedy, Alan R.; Mulvey, Robert E.

doi:10.1002/anie.200501560

Cited by 88 publications

(48 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This slight but significant difference in the chemical shifts indicates that, although part of a lithium−zinc compound, the methyl groups retain much of their original “zinc-character”. 22 In addition the 7 Li NMR spectrum of 4 showed a sharp resonance at 0.72 ppm which differs substantially to that found for the homometallic lithium compound 3 . Remarkably the chemical shifts of the aromatic signals in the 1 H and 13 C NMR spectra of 4 show little variation in comparison with those found for 3 , where the major difference found is for the metalated ortho-carbon in the 13 C NMR spectrum which appears slightly more shielded in 4 (154.8 ppm) than in 3 (159.2 ppm).…”

Section: Resultsmentioning

confidence: 58%

Closer Insight into the Reactivity of TMP−Dialkyl Zincates in Directed ortho-Zincation of Anisole: Experimental Evidence of Amido Basicity and Structural Elucidation of Key Reaction Intermediates

et al. 2009

Self Cite

View full text Add to dashboard Cite

The new dialkyl(aryl) lithium zincates [(THF)2Li(C6H4−OMe)MeZnMe] (4), [(TMEDA)Li(C6H4−OMe)MeZnMe] (6), [(THF)3Li(C6H4−OMe)tBuZntBu] (7), and [(PMDETA)Li(C6H4−OMe)tBuZntBu] (8) have been prepared by co-complexation reactions of lithiated anisole with the relevant dialkylzinc compound and the relevant Lewis base. These new heterobimetallic compounds have been characterized in solution using 1H, 13C{H}, and 7Li NMR spectroscopy, and the molecular structures of 6 and 8 have been elucidated by X-ray crystallography. In 6 the distinct metals are connected through the anisole ligand which binds in an ambidentate fashion (through carbon−zinc and oxygen−lithium contacts) and also through one of the methyl groups, to close a [LiOCCZnC] six-membered ring; whereas 8 displays an open structure where anisole connects the two metals (in the same mode as in 6) but with the tert-butyl groups exclusively bonded terminally to zinc. Reactivity studies of zincates 4 and 7 with the amine TMP(H) supply experimental evidence that these heterobimetallic compounds are intermediates in the two-step deprotonation reaction of anisole by TMP−dialkyl zincates and show the relevance of the alkyl groups in the efficiency of TMP−dialkyl zincate bases. In addition, important solvent effects have also been evaluated. When hexane is added to THF solutions of compounds 4 or 7, the homoleptic tetraorganozincate [(THF)2Li2Zn(C6H4−OMe)4] (5) is obtained as the result of a disproportionation process. This lithium-rich zincate has also been spectroscopically and crystallographically characterized.

show abstract

Section: Resultsmentioning

confidence: 58%

Closer Insight into the Reactivity of TMP−Dialkyl Zincates in Directed ortho-Zincation of Anisole: Experimental Evidence of Amido Basicity and Structural Elucidation of Key Reaction Intermediates

et al. 2009

Self Cite

View full text Add to dashboard Cite

show abstract

“…Ellipsoids are shown at 50% probability level and all hydrogen atoms and minor disordered components of TMP and tBu groups have been removed for clarity. Notably, the molecular structure shows no evidence of ligand redistribution to give either higher order zincate species or homometallic complexes such as seen previously when utilising the related zincate base TMEDA·Li(-TMP)(-nBu)Zn(nBu); 19 or intermolecular aggregation (via K--arene interactions) as witnessed when ferrocene was metalated using a related potassium zincate base. 23 Next, complexes 1 and 2 were probed in C 6 D 12 solution via NMR spectroscopy.…”

mentioning

confidence: 68%

Structurally Defined Zincated and Aluminated Complexes of Ferrocene Made by Alkali-Metal Synergistic Syntheses

et al. 2015

Self Cite

View full text Add to dashboard Cite

This version is available at https://strathprints.strath.ac.uk/51790/ Strathprints is designed to allow users to access the research output of the University of Strathclyde. Unless otherwise explicitly stated on the manuscript, Copyright © and Moral Rights for the papers on this site are retained by the individual authors and/or other copyright owners. Please check the manuscript for details of any other licences that may have been applied. You may not engage in further distribution of the material for any profitmaking activities or any commercial gain. You may freely distribute both the url (https://strathprints.strath.ac.uk/) and the content of this paper for research or private study, educational, or not-for-profit purposes without prior permission or charge.Any correspondence concerning this service should be sent to the -6 have also been studied by solution NMR spectroscopic studies.

show abstract

“…Six of these structures contain TMEDA as the coordinatively filling donor ligand. Three of these [(TMEDA) • LiZn(μ-N i Pr 2 )(μ-t Bu)( t Bu)] 56 [58], [(TMEDA) • LiZn(μ-TMP)(μ-Me)(Me)] 57 [59], and [(TMEDA) • LiZn(μ-TMP)(μ-n Bu)( n Bu)] 58 [60] adopt a standard binuclear motif (compare the general structure depicted in Figure 5 [53]. The other two crystallographically characterized zincates in this class are unusual special cases.…”

Section: Mixed Lithium-zinc Complexesmentioning

confidence: 99%

“…15 A selection of crystallographically distinct heteroleptic lithium zincates[53,[57][58][59][60][61][62][63].…”

mentioning

confidence: 99%

Mixed Lithium Complexes: Structure and Applicationin Synthesis

Mulvey

O’Hara

2014

Lithium Compounds in Organic Synthesis

Self Cite

View full text Add to dashboard Cite

IntroductionFor half a century, organolithium (C-Li bonded) reagents and lithium amides (N-Li bonded) have played a pivotal role in the development of modern day synthetic chemistry. Reagents in these categories, in particular the butyllithiums (the normal-, secondary-, and tertiary-isomers), lithium diisopropylamide (LDA), lithium 2,2,6,6-tetramethylpiperid-1-ide (LiTMP), and lithium 1,1,1,3,3,3-hexamethyldisilazide (LiHMDS) are utilized in most synthetic laboratories around the world and are especially important in the metallation reaction (that is, the conversion of a relatively inert C-H bond into a more reactive (more chemically pliable) C-Li bond) and in the kinetically operative metal-halogen exchange reactions. The past two decades have witnessed several new classes of constitutionally more complex reagents that contain multimetal and/or multianion formulations that have challenged the dominance of these unimetallic/unianionic reagents in deprotonative/metal-halogen exchange chemistry. This chapter covers some of the rich structural and synthetic chemistry of these new and still emerging systems, detailing only a small selection of what these classes of compounds can offer the chemist at the present time. Structural Chemistry of Heterometallic Lithium ComplexesStructure is inextricably and mutually linked to reactivity; hence, much recent research activity has focused on the elucidation of solid-state and solution structures of lithium organometallics and amides. This section concentrates on the structural chemistry of lithium-containing mixed-metal complexes, focusing particularly on mixed s-block (Group 1/Group 1 or Group 1/Group 2) complexes, and those containing the Group 12 d 10 metal zinc, which is commonly regarded as a displaced alkaline earth metal. In recent years, heterometallic sodium reagents (particularly sodium zincates, magnesiates, aluminates, etc.) have received a great Lithium Compounds in Organic Synthesis: From Fundamentals to Applications, First Edition. Edited by Renzo Luisi and Vito Capriati.

show abstract

Alkali‐Metal‐Mediated Zincation of Ferrocene: Synthesis, Structure, and Reactivity of a Lithium Tmp/Zincate Reagent

Cited by 88 publications

References 24 publications

Closer Insight into the Reactivity of TMP−Dialkyl Zincates in Directed ortho-Zincation of Anisole: Experimental Evidence of Amido Basicity and Structural Elucidation of Key Reaction Intermediates

Closer Insight into the Reactivity of TMP−Dialkyl Zincates in Directed ortho-Zincation of Anisole: Experimental Evidence of Amido Basicity and Structural Elucidation of Key Reaction Intermediates

Structurally Defined Zincated and Aluminated Complexes of Ferrocene Made by Alkali-Metal Synergistic Syntheses

Mixed Lithium Complexes: Structure and Applicationin Synthesis

Contact Info

Product

Resources

About