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Abstract The design and synthesis of persistent tetraaryl[4]cumulenes are reported. Derivatives with phenyl endgroups ([4]Phand[4]Ph/Ar*) are susceptible to reactions during synthesis and/or purification that complicate isolation of the desired product, particularly intermolecular dimerization reactions. Incorporation of (3,5‐di‐tert‐butyl)phenyl endgroups (Ar*) provides increased stability, culminating in the stable and isolable [4]cumulene[4]Ar*. Cumulene[4]Ar*remains, however, susceptible to dimerization under pressing conditions, and[4]Ar*also readily reacts with electrophiles under mild conditions that lead to intramolecular cyclization. Given the structural complexity of the side products in these studies (compounds3,10,14,17,18), X‐ray crystallography plays a vital role in their identification.
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Synthesis and Photophysical Properties of Soluble N‐Doped Rubicenes via Ruthenium‐Catalyzed Transfer Hydrogenative Benzannulation
Abstract Ruthenium‐catalyzed butadiene‐mediated benzannulation enabled the first synthesis of 3,10‐(di‐tert‐butyl)rubicene and its N‐doped derivatives as well as preliminary studies on their photophysical properties. Unlike the parent rubicene and 3,10‐(di‐tert‐butyl)rubicene, which adopt classical herringbone‐type packing motifs in the solid state, the N‐doped congener7 bdisplayed columnar packing with an alternating co‐facial arrangement of aromatic and heteroaromatic substructures.
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- PAR ID:
- 10235923
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 27
- Issue:
- 15
- ISSN:
- 0947-6539
- Format(s):
- Medium: X Size: p. 4898-4902
- Size(s):
- p. 4898-4902
- Sponsoring Org:
- National Science Foundation
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