One‐step Annulation/Chlorination towards Chlorinated Diphenanthro, Dibenzophenanthro, and Dichrysenothiophens

Abstract

One‐step Scholl and chlorination reactions on fourteen polyaryl thiophenes offered regioselective preparations of chlorinated diphenanthro‐, dibenzophenanthro‐, dichrysenothiophenes derivatives. Specific annulating patterns and the positions of chlorination in these polyheteroaromatics were confirmed by single‐crystal X‐ray analyses for the selected ones. Despite being twisted in their molecular frameworks, these derivatives packed into near‐perfect face‐to‐face styles.

Steering Scholl Oxidative Heterocoupling by Tuning Topology and Electronics for Building Thiananographenes and Their Functional N−/C−Congeners

“…[6] In contrast to previous reports, we could not observe oligomerization or polymerization of DPTs 6 a-b that have open 6,12-positions. [23,24] They were stable over a long duration (up to 24 h, vide-infra) under the tested oxidative conditions and were isolable in good quantities.…”

“…[20][21][22] Particularly, tetraarylthiophenes (TATs) giving thiananographenes can be cited (Figure 1b). [4,23,24] Examples with TATs highlight CÀ C bond formation between two aryl units substituted at the thiophene αand β-positions (Figure 1b). However, a pressing concern is that SOC is sensitive to the substrate design (topology), [25][26][27] electronics of the cyclizing aryl partners, [28][29][30][31][32] reagents, and reaction conditions.…”

“…However, a pressing concern is that SOC is sensitive to the substrate design (topology), [25][26][27] electronics of the cyclizing aryl partners, [28][29][30][31][32] reagents, and reaction conditions. [16,17] As evidenced, tetraphenylthiophene (TPT) under oxidative conditions failed to yield simple diphenanthro[9,10b:9',10'-d]thiophene (DPT), [4,23,24] a simple thiananographene. Most reports have bypassed this by introducing blocking groups (R) or by choosing annulated aryl units at the reactive sites (Figure 1b).…”

From Serendipity to Precision: Decoding the Enigma of Rearrangement in Scholl-Type Reactions for Programmable Cyclization

“…Based on these findings, we conclude the following: (i) Intramolecular oxidative aromatic coupling is influenced by the electronic properties of the aryl groups, (ii) Arenoannulation at thiophene [ c ]-face is challenging, and (iii) Regardless of the position of the α-/β-naphthyl groups on the thiophene unit, oxidative cyclization prevails over rearrangement.…”

“…To find answers to these questions, we have designed and synthesized regioisomeric tetraarylthiophenes (TATs, pages S3–25) with electronically graded cyclizing aryls and α-/β-naphthyl units following our recent protocols . Based on the success with double cyclodehydrogenation of TATs, we hypothesized that the electron-poor aryl groups on TATs would be reluctant toward oxidative cyclodehydrogenation (unlike electron-rich arenes) when combined with α-/β-naphthyl groups or among themselves. This strategic design should allow us to investigate any potential rearrangement, specifically the 1,2-naphthyl shift at the α- or β-positions of the thiophene unit, which may compete with cyclization in TATs ultimately enroute to rearranged-cyclized products in a predictable way.…”