Isolation of Macrocyclic Metacyclophanes From the Attempted Synthesis of [7.0]Metacyclophanes of the Myricanone Series by Thorpe-Ziegler - Intramolecular Cyclization of Diaryls Substituted by ω-Cyanoalkyl Chains

Abstract

The syntheses of the diaryls 14 and 21, substituted by two ω‐cyanoalkyl chains (one on each ring), are described. Treatment of the unsymmetrical diaryl 14 with NaN(Me)Ph in a Thorpe‐Ziegler reaction failed to give any definite product. Under the same conditions the symmetrical diaryl 21 led to an isomeric mixture of dimeric enaminonitriles 24. Mild acidic hydrolysis of the latter yielded the isomeric β‐ketonitriles 25, whereas more drastic hydrolytic conditions led to the macrocyclic diketone 26.

Formal Synthesis of (–)‐Perhydrohistrionicotoxin Using a Thorpe‐Ziegler Cyclization Approach. Synthesis of Functionalized Aza‐Spirocycles

“…Next, we investigated the formation of the C7‐C8 bond through a Thorpe‐Ziegler annulation sequence. This transformation is typically accomplished in the presence of various organic or mineral bases such as: t BuOK, morpholine, K 2 CO 3 , sodium methyl phenyl amide, LiHMDS, NaNH 2 , while Murahashi accomplished this cyclization under base‐free conditions by iridium hydride complex catalysis . However, based on our previous experiments, we believed that LDA should remain the base of choice to perform the reaction under non‐epimerizing conditions …”

Recent Advances in the Synthesis of Diarylheptanoids

“…In the first strategy, [137] challenges arise from ring strain during the closure step, resulting in occasional failure to achieve the desired cyclic diarylheptanoids. [138][139][140] Conversely, the second strategy has demonstrated success through the application of aromatic nucleophilic substitutions (SNAr) [141][142][143] both classical [134,139,[144][145][146][147] and modified Ullmann reaction [148] conditions in the synthesis of diarylether heptanoids. Research articles that are published from 2013 to 2023 on the synthesis of diarylether heptanoids are discussed in the following section.…”

“…The first method involves etherification followed by ring closure, while the second approach entails crafting suitably substituted 1,7‐diarylheptanes, followed by the etherification of linear diarylheptanes. In the first strategy, [137] challenges arise from ring strain during the closure step, resulting in occasional failure to achieve the desired cyclic diarylheptanoids [138–140] . Conversely, the second strategy has demonstrated success through the application of aromatic nucleophilic substitutions (SNAr) [141–143] both classical [134,139,144–147] and modified Ullmann reaction [148] conditions in the synthesis of diarylether heptanoids.…”

Spin‐Vibronic Coupling Controls the Intersystem Crossing of Iodine‐Substituted BODIPY Triplet Chromophores

“…The authors have cited an additional reference within the Supporting Information. [71] Author Contributions J. D.: data curation, analysis, synthetic investigation, methodology, writing -original draft. A. P.: analysis, investigation, methodology, validation, writing -review and editing.…”