A Highly Symmetric Sixfold Cycloaddition Product of Fullerene C<sub>60</sub>

Kräutler, Bernhard; Maynollo, Josef

doi:10.1002/anie.199500871

Cited by 86 publications

(34 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…808. IR (KBr): 2998w, 2922w, 1595m, 1564w, 1415s, 1359s, 1320m, 1287w, 1223w, 1172s, 981m, 956s, 887m, 855s, 815m, 740w, 646w, 604s, 3',3'-Di(pyridin-4-yl)-3'H-cyclopropa [1,9](C 60 -I h ) [5,6]fullerene (7). To C 60 (0.35 g, 0.49 mmol) and 3 (0.13 g, 0.64 mmol) in PhMe (300 ml), DBU (74 mg, 0.49 mmol) was added dropwise under N 2 , and the mixture was stirred for 7 h at 208.…”

Section: Experimental Partmentioning

confidence: 99%

Hexakis-Adducts of [60]Fullerene with Different Addition Patterns: Templated Synthesis, Physical Properties, and Chemical Reactivity

Bourgeois

Woods

Cardullo

et al. 2001

HCA

View full text Add to dashboard Cite

Representatives of two classes of hexakis-adducts of C 60 were prepared by templated synthesis strategies. Compound 8 with a dipyridylmethano addend in a pseudo-octahedral addition pattern was obtained by DMAtemplated addition (DMA 9,10-dimethylanthracene; Scheme 1) and served as the starting material for the first supramolecular fullerene dimer 2. Hexakis-adduct 12 also possesses a pseudo-octahedral addition pattern and was obtained by a sequence of tether-directed remote functionalization, tether removal, and regioselective bis-functionalization (Scheme 2). With its two diethynylmethano addends in trans-1 position, it is a precursor for fascinating new oligomers and polymers that feature C 60 moieties as part of the polymeric backbone ( Fig. 1).With the residual fullerene p-electron chromophore reduced to a cubic cyclophane-type sub-structure (Fig. 4), and for steric reasons, 8 and 12 no longer display electrophilic reactivity. As a representative of the second class of hexakis-adducts, (AE)-1, which features six addends in a distinct helical array along an equatorial belt, was prepared by a route that involved two sequential tether-directed remote functionalization steps (Schemes 3 and 5). In compound (AE)-1, p-electron conjugation between the two unsubstituted poles of the carbon sphere is maintained via two (E)-stilbene-like bridges (Fig. 4). As a result, (AE)-1 features very different chemical reactivity and physical properties when compared to hexakis-adducts with a pseudo-octahedral addition pattern. Its reduction under cyclic voltammetric conditions is greatly facilitated (by 570 mV), and it readily undergoes additional, electronically favored Bingel additions at the two sterically well-accessible central polar 6-6 bonds under formation of heptakis-and octakis-adducts, (AE)-30 and (AE)-31, respectively (Scheme 6). The different extent of the residual p-electron delocalization in the fullerene sphere is also reflected in the optical properties of the two types of hexakis-adducts. Whereas 8 and 12 are bright-yellow (end-absorption around 450 nm), compound (AE)-1 is shiny-red, with an end-absorption around 600 nm. This study once more demonstrates the power of templated functionalization strategies in fullerene chemistry, providing addition patterns that are not accessible by stepwise synthetic approaches.1. Introduction. ± Among the higher adducts of buckminsterfullerene (C 60 ; for a recent example, see [1]), hexakis-adducts are increasingly attracting interest as threedimensional scaffolds for advanced materials applications [2] [3]. Among those, derivatives with a pseudo-octahedral (T h ) addition pattern have been the earliest and most widely investigated ones [4 ± 8]. Also known is a hexakis-adduct with a D 3 -symmetrical addition pattern [2]. Both types of hexakis-adducts are accessible by stepwise additions, and their addends are evenly distributed over the entire carbon sphere. In this paper, we describe the synthesis of new hexakis-adducts with the T hsymmetrical addition pattern, which are useful...

show abstract

Section: Experimental Partmentioning

confidence: 99%

Hexakis-Adducts of [60]Fullerene with Different Addition Patterns: Templated Synthesis, Physical Properties, and Chemical Reactivity

Bourgeois

Woods

Cardullo

et al. 2001

HCA

View full text Add to dashboard Cite

show abstract

“…The underlying need for regiocontrol has provoked extensive studies on i) the patterns of the inherent reactivity of [5,6]fullerene C 60 (1) and its mono-adducts [8] [20], as well as complementary investigations on ii) how the reactions at the C-sphere can be directed further from outside [6] [8]. Tetherdirected remote functionalization [6] [21] and topochemical control in the solid state [22] have opened new ways to achieve highly selective multiple addition reactions [8].…”

mentioning

confidence: 99%

The Orthogonal (e,e,e)‐Tris‐Adduct of 9,10‐Dimethylanthracene with C₆₀‐Fullerene: A Hidden Cornerstone of Fullerene Chemistry. Preliminary Communication

Duarte-Ruiz¹,

Wurst²,

Kräutler³

2008

Helvetica Chimica Acta

Self Cite

View full text Add to dashboard Cite

Tris(9',10]ethanoanthracene [11',12': 1,9;11'',12'': 16,17;11''',12''': 30,31]) [5,6]fullerene C 60 , the orthogonal (e,e,e)-tris-adduct of C 60 and 9,10-dimethylanthracene, was obtained from [4 þ 2]-cycloaddition (Diels -Alder reaction) at room temperature. The thermally unstable orange red (e,e,e)-tris-adduct was purified by chromatography and was isolated in the form of red monoclinic crystals. Its C 3 -symmetric addition pattern was established spectroscopically. Its structure could be further investigated by single crystal X-ray diffraction. The (e,e,e)-tris-adduct of C 60 and 9,10-dimethylanthracene has earlier been suggested as intermediate and reversibly formed critical component in template directed addition reactions of C 60 . This previously elusive compound has now been isolated and structurally characterized.Introduction. -The discovery of the fullerenes [1] and of an efficient method to produce substantial amounts of these spherical carbon molecules [2] has opened a new era of chemistry [1] [3 -5] and has paved the way to synthetic, spectroscopic, and structural studies [6]. One major goal of these studies concerned the exploration of methods to achieve specific exohedral modifications of the symmetric spherical C- . In other cases, the thermal reversibility was exploited to achieve reversible attachment of fullerenes to solid support [19].As the highly symmetrical C-sphere provided by the [5,6]fullerene 1 represents a unique basis for building up three dimensional molecular structures by multiple exohedral functionalization, particular attention was paid to the problem of regioselectivity in functionalization reactions [7] [8]. The underlying need for regiocontrol has provoked extensive studies on i) the patterns of the inherent reactivity of [5,6]fullerene

show abstract

“…Even though the regiochemistry of Diels-Alder additions is low, a few exceptions have been reported. In this regard, the reaction of C 60 with an excess of 2,3-dimethyl-1,3-butadiene at elevated temperatures yields a hexakis-adduct with T h symmetry with an average effective selectivity >80% for each addition step [52].…”

Section: Retro-diels-alder Reactionmentioning

confidence: 99%

Buckyballs

Delgado

Filippone

Giacalone

et al. 2013

Topics in Current Chemistry

View full text Add to dashboard Cite

Buckyballs represent a new and fascinating molecular allotropic form of carbon that has received a lot of attention by the chemical community during the last two decades. The unabating interest on this singular family of highly strained carbon spheres has allowed the establishing of the fundamental chemical reactivity of these carbon cages and, therefore, a huge variety of fullerene derivatives involving [60] and [70]fullerenes, higher fullerenes, and endohedral fullerenes have been prepared. Much less is known, however, of the chemistry of the uncommon non-IPR fullerenes which currently represent a scientific curiosity and which could pave the way to a range of new fullerenes. In this review on buckyballs we have mainly focused on the most recent and novel covalent chemistry of fullerenes involving metal catalysis and asymmetric synthesis, as well as on some of the most significant advances in supramolecular chemistry, namely H-bonded fullerene assemblies and the search for efficient concave receptors for the convex surface of fullerenes. Furthermore, we have also described the recent advances in the macromolecular chemistry of fullerenes, that is, those polymer molecules endowed with fullerenes which have been classified according to their chemical structures. This review is completed with the study of endohedral fullerenes, a new family of fullerenes in which the carbon cage of the fullerene contains a metal, molecule, or metal complex in the inner cavity. The presence of these species affords new fullerenes with completely different properties and chemical reactivity, thus opening a new avenue in which a more precise control of the photophysical and redox properties of fullerenes is possible. The use of fullerenes for organic electronics, namely in photovoltaic applications and molecular wires, complements the study and highlights the interest in these carbon allotropes for realistic practical applications. We have pointed out the so-called non-IPR fullerenes - those that do not follow the isolated pentagon rule - as the most intriguing class of fullerenes which, up to now, have only shown the tip of the huge iceberg behind the examples reported in the literature. The number of possible non-IPR carbon cages is almost infinite and the near future will show us whether they will become a reality.

show abstract

A Highly Symmetric Sixfold Cycloaddition Product of Fullerene C₆₀

Cited by 86 publications

References 50 publications

Hexakis-Adducts of [60]Fullerene with Different Addition Patterns: Templated Synthesis, Physical Properties, and Chemical Reactivity

Hexakis-Adducts of [60]Fullerene with Different Addition Patterns: Templated Synthesis, Physical Properties, and Chemical Reactivity

The Orthogonal (e,e,e)‐Tris‐Adduct of 9,10‐Dimethylanthracene with C₆₀‐Fullerene: A Hidden Cornerstone of Fullerene Chemistry. Preliminary Communication

Buckyballs

Contact Info

Product

Resources

About

A Highly Symmetric Sixfold Cycloaddition Product of Fullerene C60

Cited by 86 publications

References 50 publications

Hexakis-Adducts of [60]Fullerene with Different Addition Patterns: Templated Synthesis, Physical Properties, and Chemical Reactivity

Hexakis-Adducts of [60]Fullerene with Different Addition Patterns: Templated Synthesis, Physical Properties, and Chemical Reactivity

The Orthogonal (e,e,e)‐Tris‐Adduct of 9,10‐Dimethylanthracene with C60‐Fullerene: A Hidden Cornerstone of Fullerene Chemistry. Preliminary Communication

Buckyballs

Contact Info

Product

Resources

About

A Highly Symmetric Sixfold Cycloaddition Product of Fullerene C₆₀

The Orthogonal (e,e,e)‐Tris‐Adduct of 9,10‐Dimethylanthracene with C₆₀‐Fullerene: A Hidden Cornerstone of Fullerene Chemistry. Preliminary Communication