The key for the synthesis of a triply twisted MCNB relies on the control of both twist and strain, and a suitable reaction to form double-stranded fully conjugated structure. We recently demonstrated that Bi(OTf)3-mediated cyclization of vinyl ethers was an efficient benzannulation reaction for the synthesis of double-stranded kekulene, cycloarenes, and expanded kekulenes. This reaction was also successfully applied for the synthesis a twisted carbon nanobelt with a figure-eight geometry. In that case, pre-organization of each constitutional aromatic unit and vinyl ether group in the semi-rigid precursor allows regioselective cyclization to form a rigid, double-stranded carbon nanobelt with two half twists. Encouraged by these successful examples, we designed a synthetic strategy for a triply twisted MCNB (1, Fig. ) based on the following considerations: (i) To control the conformation at each twist, two key building blocks, a C2 symmetric 5,6,12,13-tetrahydrobenzo[k]tetraphene (THBT) with two Bpin groups at 2,9-positions (4) and a 1,3-dibromobenzene carrying two vinyl ether groups at 2,4-positions (5), were chosen. Such design would allow the formation of a semi-rigid macrocycle (3a or 3b) with three-fold symmetry after Suzuki coupling reactions. Due to the steric hindrance between the vinyl ether groups and the nearby THBT units, the dihydronaphthalene moieties in 4 that linked to the benzene ring in 3 could adopt an alternating "up" and "down" orientation relative to the mean plane of the macrocycle to partially release the strain. In fact, DFT calculations also predict that this triply twisted structure has lower energy (about 5.3 kcal/mol) than the other conformer (Fig. in Supplementary Information). Such a preorganization would lead to regio-selective cyclization of vinyl ethers to the specific carbon sites on the THBT units (highlighted in Fig. ) at the next step to give a more rigid, double-stranded macrocycle (2a or 2b). (ii) To avoid possible problems arisen from the large strain during the benzannulation step, two sp 3 -hybridized ethylene units rather than sp 2 -carbon-carbon double bonds are introduced in the building block 4. This would result in less strain in the nanobelt 2a/2b as compared to the fully conjugated MCNB 1. Conversion of 2a/2b to 1 could be done by aromaticity-driven oxidative dehydrogenation reaction at the last step. (iii) To balance solubility and crystallinity, n-butoxy (5a) or n-octyloxy (5b) is introduced onto the building block. The former substituent allows us to obtain single crystals of the key intermediate 2a, while the latter endows sufficient solubility of the final MCNB 1 for isolation as well as growth of single crystals. The red and green dots in 3a/3b highlight the cyclization sites on the benzene rings that bent outward ("up") and inward ("down") the paper plane, respectively. The optimized geometry of 3a/3b (in which the alkoxy groups are replaced by methoxy during the calculation) is also shown, with the pink arrows indicating the regio-selective electrophilic cyclization.