Synthesis and structures of 1,3,1′,3′-tetrabenzyl-2,2′-biimidazolidinylidenes (electron-rich alkenes), their aminal intermediates and their degradation products

Çetınkaya, Bekır; Çetinkaya, Engin; Chamizo, José Antonio; Hitchcock, Peter B.; Jasim, Hatam A.; Küçükbay, Hasan; Läppert, Michael F.

doi:10.1039/a802123f

Cited by 67 publications

(25 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…When a larger proportion of halogen is employed, only uncharacterized decomposition products are obtained, probably due to halogenation of the alkyl side-chains. [34] ( 14) A different reaction path is observed with iodine. In this case, addition of a stoichiometric amount of halogen affords the intermediate charge-transfer complex 5, whose molecular structure has been established by XRD.…”

Section: Reactivitymentioning

confidence: 91%

See 1 more Smart Citation

Betaine Adducts of N‐Heterocyclic Carbenes: Synthesis, Properties, and Reactivity

2009

View full text Add to dashboard Cite

N‐Heterocyclic carbenes (NHCs) form stable zwitterionicadducts with a range of heteroallenes, ketenes, and allenes. Although the first representatives of this class of inner salts were first investigated as far back as the 1960s, they have enjoyed a sustained interest from the chemical community over the years. Depending on the nature of their anionic moiety, NHC betaines display a very broad palette of reactivities and have found applications in various fields of organic synthesis and catalysis. In this Microreview, the synthesis, properties, and reactivity of NHC betaines are surveyed. The NHCs under consideration include ylidenes derived from imidazole, benzimidazole, imidazoline, thiazole, or triazole, and the heteroallenes investigated so far are carbon dioxide, carbon disulfide, isocyanates, isothiocyanates, and their selenium analogues. A historical background is provided for each type of adduct under consideration, but emphasis is placed mainly on developments that have appeared in the literature within the past few years. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

show abstract

Section: Reactivitymentioning

confidence: 91%

“…Carbenes also form stable, neutral adducts with a variety of organic species, including alcohols, [13] amines, [14] and chloroform. [15] The reaction proceeds via insertion of the carbene into a labile H-Z bond and is thermally reversible [Equation (2)].…”

Section: Introductionmentioning

confidence: 99%

Betaine Adducts of N‐Heterocyclic Carbenes: Synthesis, Properties, and Reactivity

2009

View full text Add to dashboard Cite

show abstract

“…Similar rearrangement reactions have been reported for 1,3,1',3'-tetraallyl-2,2'-biimidazolidinylidene [115] and 1,3,1',3'-tetrabenzyl-2,2'-bibenzimidazolinylidene. [116] 2.3.5. Thiazolin-2-ylidenes and Benzothiazolin-2-ylidenes…”

Section: Benzimidazolin-2-ylidenes and Related Benzannulated Compoundsmentioning

confidence: 98%

Heterocyclic Carbenes: Synthesis and Coordination Chemistry

2008

View full text Add to dashboard Cite

The chemistry of heterocyclic carbenes has experienced a rapid development over the last years. In addition to the imidazolin-2-ylidenes, a large number of cyclic diaminocarbenes with different ring sizes have been described. Aside from diaminocarbenes, P-heterocyclic carbenes, and derivatives with only one, or even no heteroatom within the carbene ring are known. New methods for the synthesis of complexes with N-heterocyclic carbene ligands such as the oxidative addition or the metal atom template controlled cyclization of beta-functionalized isocyanides have been developed recently. This review summarizes the new developments regarding the synthesis of N-heterocyclic carbenes and their metal complexes.

show abstract

“…[4][5][6] Nolan et al have concluded from structural and thermochemical studies that these NHCs exhibit a similar σ-donor and low π-acceptor ability as phosphanes in metal coordination chemistry, and they have been demonstrated to have additional advantages to the widely used phosphane ligands. [7,8] Lappert et al have investigated a type of (CH 2 ) n -bridged Arduengo carbene analogue, namely tetraaminoalkenes (enetetramines I), [9][10][11] in detail and have prepared the NHC Mo and Rh complexes of these enetetramines. [12][13][14] Later, Chen found that the bond-dissociation enthalpy of these enetetramines is only slightly larger than zero by thermochemical studies, thus indicating the existence of a very weak C=C bond in the formal dimers of singlet carbenes II.…”

Section: Introductionmentioning

confidence: 99%

Synthetic and Structural Studies of Silver(I)‐ and Gold(I)‐ContainingN‐Heterocyclic Carbene Metallacrown Ethers

Wang

Liu

et al. 2006

Eur J Org Chem

View full text Add to dashboard Cite

The ligands bis(imidazolium) hexafluorophosphate [RHimy-(CH 2 OCH 2 ) n -HimyR] [PF 6 ] 2 [Himy = -C 3 N 2 H 3 -, imidazolium; R = 1-naphthylmethyl, n = 2 (1a), 3 (2a); R = 9-anthracenylmethyl, n = 2 (1b), 3 (2b)] with a highly flexible polyether chain were easily prepared by the reaction of substituted imidazole with the corresponding polyglycol diiodide, followed by exchange of the anions with PF 6 -. Ligands 1a,b and 2a,b react with Ag 2 O to give monometallic Ag I -containing N-heterocyclic carbene (NHC) metallacrown ethers 3a,b and 4a,b with a long and highly flexible bridging chain (CH 2 OCH 2 ) n (n = 2, 3) between the two imidazolium units. Complexes

show abstract

Synthesis and structures of 1,3,1′,3′-tetrabenzyl-2,2′-biimidazolidinylidenes (electron-rich alkenes), their aminal intermediates and their degradation products

Cited by 67 publications

References 16 publications

Betaine Adducts of N‐Heterocyclic Carbenes: Synthesis, Properties, and Reactivity

Betaine Adducts of N‐Heterocyclic Carbenes: Synthesis, Properties, and Reactivity

Heterocyclic Carbenes: Synthesis and Coordination Chemistry

Synthetic and Structural Studies of Silver(I)‐ and Gold(I)‐ContainingN‐Heterocyclic Carbene Metallacrown Ethers

Contact Info

Product

Resources

About