Programmable zigzag π-extension toward graphene-like molecules by the stacking of naphthalene blocks

Nitrogen Effects Endowed by Doping Electron-Withdrawing Nitrogen Atoms into Polycyclic Aromatic Hydrocarbon Fluorescence Emitters

“…These drawbacks hinder the attainment of structural and functional diversity in organic materials, particularly when it comes to incorporating peripheral units at specific positions for optimizing the material properties. From the viewpoint of synthetic simplicity and atom economy, transition-metal-catalyzed annulation with alkynes through chelation-assisted C–H activation is undoubtedly a streamlined protocol to furnish structurally diverse PAH structures. − A retrosynthetic analysis elucidates that 1,7-diazaperylene can be constructed via a multiple C–H annulation reaction of imine derivatives with alkynes (C2 units). The imine derivatives can, in turn, be derived from quinones, which are readily available and can serve as viable starting materials (Figure d).…”

Cobalt-Catalyzed Cascade C–H Activation/Annulation Polymerizations toward Diversified and Multifunctional Sulfur-Containing Fused Heterocyclic Polymers

“…The development of new and efficient polymerization methods based on organic reactions has greatly promoted the advancement of polymer science and materials science. As a reliable and powerful methodology in synthetic chemists’ toolbox, transition-metal-catalyzed C–H activation has received tremendous attention in past decades. − The application of C–H activation in polymer science has enabled the facile transformation of abundantly existing substrates into high-value biomacromolecules and novel functional polymer materials that were hard to obtain by traditional methods. − Attracted by the wide substrate scope, high step and atom economy, high efficiency, and environmental friendliness of C–H activation chemistry, polymer scientists have developed a series of efficient C–H activation-based polymerization and postfunctionalization strategies. − Among them, transition-metal-catalyzed polyannulation via C–H bond activation has recently emerged as a facile, economical, and innovative method for the in situ construction of multifunctional polymers with newly formed fused (hetero)­cycles as the π-spacer moieties of polymer backbones. − However, examples of such C–H activated polyannulations still remain rather limited due to the high development difficulty. The reported examples typically rely on the use of precious transition metal-based catalysts, including Rh, Pd, Re, Ru, and Ir, and the resulting polymer structures are still limited to ring-fused aromatics or nitrogen-/oxygen-containing fused heterocyclic units. , There is great demand and plenty of room for innovation in this area to explore new C–H activated polyannulation methods based on greener and inexpensive catalysts and further enrich the structural diversity and functionalities of ring-fused heteroaromatic polymers.…”

Construction of Acenaphthylenes via C−H Activation-Based Tandem Penta- and Hexaannulation Reactions

“…Dimethyl acetylenedicarboxylate (DMAD), an electron-de cient alkyne diester, is widely used in Michael reactions, cyclizations (Diels-Alder and 1,3-dipole) but rarely in transition metal-catalyzed C-H activation-annulations 49 . Recently, we demonstrated its capability in C-H activation-annulation reaction with naphthalene ketones to generate aromatic polycarboxylic esters, establishing an e cient strategy for the synthesis of graphene-like molecules by utilizing the removability of ester groups as a key point 50 .…”