Abstract
A series of meso‐trifluoromethyl‐substituted expanded porphyrins, including N‐fused [24]pentaphyrin 3, [28]hexaphyrin 4, [32]heptaphyrin 5, [46]decaphyrin 6, and [56]dodecaphyrin 7, were synthesized by means of an acid‐catalyzed one‐pot condensation reaction of 2‐(2,2,2‐trifluoro‐1‐hydroxyethyl)pyrrole (1) as the first examples bearing meso‐alkyl substituents. Besides these products, porphyrin 2 and two calix[5]phyrins 8 and 9 were also obtained. [28]Hexaphyrin 4 was quantitatively oxidized to [26]hexaphyrin 14 with MnO~2~. These expanded porphyrins have been characterized by mass spectrometry, ^1^H and ^19^F NMR spectroscopy, and UV/Vis spectroscopy. The single‐crystal structures have been determined for 3, 4, 6, 7, and 14. The N‐fused [24]pentaphyrin 3 displays a distorted structure containing a tricyclic fused moiety that is similar to those of meso‐aryl‐substituted counterparts, whereas 8 and 9 are indicated to take roughly planar conformations with an inverted pyrrole opposite to the sp^3^‐hybridized meso‐carbon atom. Both [28]‐ and [26]hexaphyrins 4 and 14 have figure‐of‐eight structures. Solid‐state structures of the decaphyrin 6 and dodecaphyrin 7 are remarkable, exhibiting a crescent conformation and an intramolecular two‐pitch helical conformation, respectively.