Polyquinolines have been studied since the early 1970s due to their favorable chemical, optical, electrical, and mechanical properties. However, surprisingly few synthetic strategies have been developed for the preparation of these polymers. Herein, we demonstrate the application of the aza-Diels–Alder (Povarov) reaction for the synthesis of soluble polyquinolines from a bifunctional monomer. Our approach furnishes polyquinolines with a unique architecture and connectivity in only two synthetic steps from inexpensive, commercially available reagents. The reported strategy may therefore represent a welcome addition to the polymer chemist’s toolkit by providing ready access to a diverse library of polyquinoline-type materials.

Graphene nanoribbons (GNRs) represent promising materials for the next generation of nanoscale electronics. However, despite substantial progress towards the bottom-up synthesis of chemically and structurally well-defined all-carbon GNRs, strategies for the preparation of their nitrogen-doped analogs remain at a nascent stage. This scarce literature precedent is surprising given the established use of substitutional doping for tuning the properties of electronic materials. Herein, we report the synthesis of a previously unknown class of polybenzoquinoline-based materials, which have potential as GNR precursors. Our scalable and facile approach employs few synthetic steps, inexpensive commercial starting materials, and straightforward reaction conditions. Moreover, due to the importance of quinoline derivatives for a variety of applications, the reported findings may hold implications across a diverse range of chemical and physical disciplines.

We report a general, modular, and high yield route to quinoline-based functional materials for applications in organic electronics.

This study describes the synthesis of modular diquinolineanthracene and polydiquinolineanthracene derivatives. The reported facile and scalable aza-Diels-Alder-based approach requires mild conditions, proceeds in two steps, uses commercially available starting materials, and accommodates varying functionalities. Given the known utility of the acene and quinoline motifs, the synthesized molecules and polymers hold promise for organic electronics applications.

Naturally occurring and recombinant protein-based materials are frequently employed for the study of fundamental biological processes and are often leveraged for applications in areas as diverse as electronics, optics, bioengineering, medicine, and even fashion. Within this context, unique structural proteins known as reflectins have recently attracted substantial attention due to their key roles in the fascinating color-changing capabilities of cephalopods and their technological potential as biophotonic and bioelectronic materials. However, progress toward understanding reflectins has been hindered by their atypical aromatic and charged residue-enriched sequences, extreme sensitivities to subtle changes in environmental conditions, and well-known propensities for aggregation. Herein, we elucidate the structure of a reflectin variant at the molecular level, demonstrate a straightforward mechanical agitation-based methodology for controlling this variant’s hierarchical assembly, and establish a direct correlation between the protein’s structural characteristics and intrinsic optical properties. Altogether, our findings address multiple challenges associated with the development of reflectins as materials, furnish molecular-level insight into the mechanistic underpinnings of cephalopod skin cells’ color-changing functionalities, and may inform new research directions across biochemistry, cellular biology, bioengineering, and optics.

Graphene nanoribbons (GNRs) are promising candidate materials for the next generation of nanoscale electronics. Described herein is the synthesis of 2,4,6-substituted benzoquinolines, which constitute building blocks for nitrogen-doped GNRs. The presented facile and modular aza-Diels-Alder chemistry accommodates the installation of diverse functionalities at the crowded benzoquinolines' 2 positions. Given the general utility of the benzoquinoline motif, these findings hold relevance not only for carbon-based electronics but also for a range of chemical disciplines.

Graphene nanoribbons (GNRs) represent promising materials for the next generation of nanoscale electronics. However,d espite substantial progress towards the bottom-up synthesis of chemically and structurally well-defined all-carbon GNRs,s trategies for the preparation of their nitrogen-doped analogs remain at an ascent stage.T his scarce literature precedent is surprising given the established use of substitutional doping for tuning the properties of electronic materials. Herein, we report the synthesis of apreviously unknown class of polybenzoquinoline-based materials,w hichh ave potential as GNR precursors.Our scalable and facile approach employs few synthetic steps,inexpensive commercial starting materials, and straightforwardr eaction conditions.M oreover,d ue to the importance of quinoline derivatives for av ariety of applications,t he reported findings may hold implications across ad iverse range of chemical and physical disciplines.Graphene nanoribbons (GNRs), which are narrow strips of graphene featuring aq uantum confinement-induced bandgap,c onstitute ap romising class of materials for the next generation of semiconductor devices.[1-10] Theelectronic properties of GNRs are exquisitely sensitive to their width, heteroatom content, and edge character. [3][4][5] Thus,m uch research effort has been devoted to the preparation of GNRs that are structurally and chemically defined at the atomic level. [6][7][8][9][10] Although traditional top-down lithographic approaches have exhibited only limited success in this regard, [6][7][8][9][10] more recent studies have demonstrated the bottom-up preparation of pristine GNRs via the surfaceassisted [11][12][13][14][15][16][17][18][19][20][21][22] or solution-phase [23][24][25][26][27][28][29][30][31][32] synthesis of nanoribbon precursor polymers,followed by their cyclodehydrogenation. To date,these bottom-up strategies have primarily focused on all-carbon systems,w ith only al imited number of studies describing the preparation of nitrogen-containing GNR frameworks. [20-22, 31, 32] Given the immense potential of substitutional nitrogen doping for tailoring the propertieso f GNRs,the sparse literature precedent is surprising and likely arises from the challenges associated with the incorporation of heteroatoms at arbitrary locations in graphitic materials. [33,34] Herein, we describe the modular synthesis of polybenzoquinolines,which constitute ageneric class of GNR precursor polymers,and, to the best of our knowledge,have never been previously reported. We first develop general aza-DielsAlder reaction conditions for the synthesis of as eries of benzoquinoline model compounds.Subsequently,weprepare an AB-type bifunctional monomer and use the conditions validated for the model compounds to synthesize acongested polybenzoquinoline via aD iels-Alder-type polymerization reaction. [35][36][37] We in turn demonstrate the scope and modularity of our methodology by preparing polybenzoquinolines of various sizes that feature different peripheral substituents. Overa...

We have validated a general strategy for the synthesis of chloro-containing quinoline, benzoquinoline and polybenzoquinoline variants.