Synthesis and Characterization of Functionalized [12]Cycloparaphenylenes Containing Four Alternating Biphenyl and Naphthyl Units

Abstract

Functionalized [12]cycloparaphenylenes ([12]CPPs) containing four alternating biphenyl and naphthyl units were synthesized. A macrocyclic furan-containing CPP precursor was used for the Diels-Alder reaction with the parent benzyne or 3,6-dimethoxybenzyne to form the corresponding macrocyclic carbon frameworks. The subsequent reductive deoxygenation of the Diels-Alder adducts with Fe(CO) followed by oxidative aromatization with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone produced the functionalized [12]CPPs. The effect of macrocyclic ring size on the reaction rate of oxidative aromatization was investigated.

Syntheses of Functionalized Cycloparaphenylenes, Furan-Containing Cycloparaphenylenes, and Related Thiophene-Containing Fused Carbon Nanohoop

“…The organic layer was then passed through a short silica gel column (10 cm high, 5 cm in diameter 4,142.3,131.9,129.7,127.2,124.8,120.6,115.1,40.8. HRMS (ESI) 2,143.3,131.1,129.4,128.8,128.1,119.4,116.0,40.9,25.6,18.2,HRMS (ESI) Experimental Procedure for II-9. To a 250-mL flask were added 5.30 g of II-7a (7.56 mmol), 4.61 g of bis(pinacolato)diboron (II-8, 18.1 mmol), 0.18 g of XPhos (0.38 mmol), and 0.08 g of Pd2(dba)3 (0.08 mmol).…”

“…[S5] A correction for secondary extinction was not applied. The value of the Flack parameter was 0.006 (2). The largest peak in the final difference electron density synthesis was 1.086 e -/Å 3 and the largest hole was -0.461 e -/Å 3 with an RMS deviation of 0.073 e -/Å 3 .…”

“…Our previous attempts to oxidatively aromatize 4H [6]CPP were not successful. 2 However, preliminary studies showed that 4H[10]CPP can be oxidatively aromatized by treatment with 2,3˗dichloro˗5,6˗dicyano˗1,4-benzoquinone (DDQ) at an elevated temperature (150 °C).…”

“…Due to their extreme diversity, richness, and unprecedented mechanical and optical properties, CNTs have become a major area of materials research. [2][3][4][5] Due to their unprecedented properties, such as thermal and electrical conductivity, [6][7][8][9] high aspect ratio, 10 high tensile strength, 11 and unique optical characteristics, [12][13][14] CNTs are perfect candidates to be considered for the next generation of materials and will be used in many different areas of technology, specifically in nanotechnology. 15 CNTs are used in various applications such as electrical wiring, 16 sensor arrays, [17][18][19][20][21] sensing, 22 biomaterials, 23 fieldeffect transistors, [24][25][26] transparent conductive films, 27 interconnect, 28 and other nanoscale applications.…”

“…The [n]CPP interior space offers unique host-guest interactions, such as hostgust interaction between [8]-[10]CPPs. [1][2][3] Additionally, (n,n) single-walled carbon nanotubes (SWCNTs) are comprised of repeating linkages of [n]CPPs. The idea of utilizing [n]CPPs as a template for a bottom-up approach to synthesizing SWCNTs was first introduced when Smalley and coworkers showed that smaller carbon nanotubes (CNTs) could act as a seed to grow longer CNTs with the same chirality and diameter.…”