Skeletal Rearrangement of Twisted Thia‐Norhexaphyrin: Multiply Annulated Polypyrrolic Aromatic Macrocycles

Abstract

Ah ybrid thia-norhexaphyrin comprising ad irectly linked N-confused pyrrole and thiophene unit (1)r evealed unique macrocycle transformations to affordm ultiply innerannulated aromatic macrocycles.Oxidation with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone triggered acleavage of the C À S bond of the thiophene unit, accompanied with skeletal rearrangement to affordu nique p-conjugated products:athiopyrrolo-pentaphyrin embedded with apyrrolo[1,2]isothiazole (2), as ulfur-free pentaphyrin incorporating an indolizine moiety (3), and at hiopyranyltriphyrinoid containing a2 Hthiopyran unit (4). Furthermore, 2 underwent desulfurization reactions to affordafused pentaphyrin containing apyrrolizine moiety (5)u nder mild conditions.U sing expanded porphyrin scaffolds,o xidative thiophene cleavage and desulfurization of the hitherto unknown N-confused core-modified macrocycles would be ap ractical approachf or developing unique polypyrrolic aromatic macrocycles.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.

Twisted-Planar-Twisted expanded porphyrinoid dimer as a rudimentary reaction-based methanol indicator

“…The first member of this ever-increasing family, the pentapyrrolic macrocycle sapphyrin 5 , was disclosed by Woodward in 1966 as being an unexpected reaction by-product. Since then, numerous expanded porphyrins have been prepared and studied in light of their flexible conformations, rich coordination chemistry, unique redox activity, and unusual chemical reactivity 6 – 8 . Often these features have no parallel in the chemistry of simple porphyrins.…”

Rational Synthesis of 5,5,5‐Tricyclic Fused Thia‐heptaphyrin (1.1.1.1.1.1.0) From a Helical Oligopyrrin Hybrid

“…Recently, we reported a thia‐norhexaphyrin ( 4 ) containing a directly linked N‐confused pyrrole‐thiophene unit (C α −C α1 ) through the oxidative cyclization of the linear thiophene‐pentapyrrole hybrid ( S‐P 5 ) with N‐confused pyrrole and thiophene units at the two terminals. 4 underwent unique macrocycle transformation reactions to afford various novel aromatic porphyrinoids . Based on this background, we envisioned that heptaphyrin 5 (Figure ) may be constructed through an oxidative ring closure reaction of the thiophene–hexapyrrole hybrid ( S‐P 6 ), which contains one more pyrrole than S‐P 5 .…”

“…4 underwent unique macrocycle transformation reactions to afford various novel aromatic porphyrinoids. [15] Based on this background, we envisioned that heptaphyrin 5 (Figure 1) may be constructed through an oxidative ring closure reaction of the thiophenehexapyrrole hybrid (S-P 6 ), which contains one more pyrrole than S-P 5 . With this consideration in mind, S-P 6 was synthesized in this work and oxidized with 2,3-dichloro-5,6-dicyano-1,4benzoquinone (DDQ), which turned out to afford a fully conjugated linear thiaheptapyrrin 1 instead of the anticipated heptaphyrin 5.…”

Second-Order Nonlinear Optics Response of the Boron-Dipyrromethenes-Based Mislinked Expanded Porphyrins: Revealing the Role of the −BF2 Group

“…* sı Supporting Information ABSTRACT: Here, the mislinked expanded porphyrins singly (labeled A) and doubly (labeled B) neo-confused [22]smaragdyrin, the boron-dipyrromethenes-based mislinked expanded porphyrins singly (labeled C) and doubly (labeled D) neo-confused [22]smaragdyrin, where both C and D include a −BF 2 group, are chosen to serve as the study objects, and theoretical calculations are carried out to study the role of the −BF 2 group in the second-order nonlinear optics (NLO) behaviors. Results highlighted that the −BF 2 group plays an important role for the second-order behaviors in mislinked expanded porphyrins; namely, embedding the −BF 2 group well enhanced the hyper-Rayleigh scattering (HRS) value {β HRS (0;0,0)}, N onlinear optics (NLO) is an important component of modern optical fields, and NLO mainly studies the phenomena generated by the interaction between light and media.…”

“…In addition, our previous works found that the mislinked expanded porphyrins can serve as a potential candidate of NLO materials 6,7 and revealed that increasing mislinked connection numbers and changing mislinked connection ways of the pyrrole units in mislinked expanded porphyrins play a significant role for tuning the NLO response. 7 Inspired by versatile diversities in structures, properties, and functions, the expanded porphyrin family is constantly being expanded by the efforts of various experimental research groups of expanded porphyrin, 8,18−22 such as the mislinked expanded porphyrins singly (labeled A) and doubly (labeled B) neo-confused [22]smaragdyrin (as shown in Figure 1) 21 and boron dipyrromethenes (BODIPYs, which includes the −BF 2 group) based mislinked expanded porphyrins singly (labeled C) and doubly (labeled D) neo-confused [22]smaragdyrin (as shown in Figure 1). 21 BODIPYs have been extensively studied because BODIPYs hold desirable photophysical properties; related studies have also disclosed that BODIPYs hold good application prospects in NLO materials, 23,24 fluorescent labels, 25,26 etc.…”