Cycloparaphenylene Double Nanohoop: Structure, Lamellar Packing, and Encapsulation of C₆₀ in the Solid State

Abstract

A new member of the cycloparaphenylene double-nanohoop family was synthesized. Its π-framework features two oval cavities that display different shapes depending on the crystallization conditions. Incorporation of the peropyrene bridge within the nanoring cycles via bay -regions alleviates steric effects and thus allows 1:1 complexation with C 60 in the solid state. This nanocarbon adopts a lamellar packing motif, and our results suggest that the structural adjustment of this double nanohoop could enable its use in supramolecular and semiconductive materials.

Photoinduced electron transfer in host–guest complexes of double nanohoops

“…Also, Juríček and co-workers [17,18] reported a new member of the double-nanohoop family (Twin2)-a giant π-conjugated framework with two CPP units linked by a peropyrene fragment (Fig. 1).…”

Fullerene Wires Assembled Inside Carbon Nanohoops

“…Structural adjustment was implemented to modify these voids and a new member of the double‐nanohoop family, CPP‐ b PP ( 2 d , Figure 1 b) was devised and synthesized. [18b] In this system, the nanoring‐cycles are connected at the bay‐regions of the central peropyrene segment and the two oval‐shaped voids have a slightly different shape in the solid state depending on the crystallization conditions. Unexpectedly, no binding interaction between 2 d and C 60 /C 70 was detected in solution, possibly due to the cavity‐reorganization energy that counteracts the host‐guest complexation energy.…”

Nonacethrene Unchained: A Cascade to Chiral Contorted Conjugated Hydrocarbon with Two sp3-Defects

“…6,28−30 In contrast, the current research is largely focused on the properties of extended diradicaloids, with efforts being made to suppress 17,30−32 their reactivity in order to obtain stable or persistent systems. A few recent reports indicate, however, that the reactivity of "unchained" diradicaloids, often regarded as an undesired or a decomposition feature, can be utilized to create function, 25,33−37 develop new methods, 38,39 and deepen our chemical concepts. 40,41 Recent examples are biphenalenylidene (BPLY, Scheme 1, top), an intermediate on the decomposition pathway of phenalenyl (PLY) reported by Kubo et al, 28,42 and cethrene, 26 a helical diradicaloid developed in our laboratory (Scheme 1, middle), which undergo a thermal 6π electrocyclization (EC).…”

“…In the past, various aspects of reactivity of these and analogous systems were subject to extensive investigations. ,− In contrast, the current research is largely focused on the properties of extended diradicaloids, with efforts being made to suppress ,− their reactivity in order to obtain stable or persistent systems. A few recent reports indicate, however, that the reactivity of “unchained” diradicaloids, often regarded as an undesired or a decomposition feature, can be utilized to create function, ,− develop new methods, , and deepen our chemical concepts. , …”