Rapid synthesis of 4-alkynyl coumarins and tunable electronic properties of emission solvatochromic fluorophores

Pd‐Catalyzed Domino Cross‐Coupling: Synthesis of Functionalized 4‐(Arylethynyl)Coumarins

“…This successful development of a combined protocol thus paved the way for a straightforward synthesis of differently functionalized 3‐aryl‐4‐(arylethynyl)coumarins. Some of these bis‐coupled coumarin derivatives embedded with aryl and alkyne functionality in 3 rd and 4 th positions may serve as excellent scaffolds for various photophysical applications [6f,13] . In that sense, our methodology easily allows the need‐based incorporation of both electron‐donating and electron‐withdrawing groups in the coumarin system for the suitable maneuvering of their photophysical properties.…”

Aggregation‐induced emission properties of pyridyl‐containing tetra‐arylethenes

“…[16][17][18][19][20][21][22] As well known, the electronic characteristic of organic fluorescent molecules greatly affects their optical properties. [23][24][25][26][27] Many organic AIE-active fluorophores have been employed to study the relationship between electronic effects and AIE properties, however these molecules usually have obvious distinct molecular structures. [28][29][30][31][32] The AIE properties of fluorophores with the same emissive core and obviously different electronic effects are rarely studied.…”

Mannich bases of hydroxycoumarins: synthesis, DFT/QTAIM computational study and assessment of biological activity

“…For these derivatives, it has been recognized that the position of the hydroxy substituents within the coumarin structure plays an important role for its biological activity [6][7][8] and, in the quest of nding a specic and oriented activity in certain pathways of neoplastic disease, some studies have been made to relate their electronic density distribution with their antineoplastic activity. 9,10 On another hand, their highly delocalized p conjugated system, their planarity, their electronic environment and the feasibility for modifying their substitution pattern, have made them extensively studied, both theoretically 11 and experimentally, resulting in a ne tuning of their electronic properties, 12 yielding interesting applications of their photophysical properties in materials chemistry and light-driven biologically signicant processes, such as photodynamic therapy (PDT) 13,14 and uorescent probes for many relevant analytes. 15 Concerning functionalized hydroxycoumarins, Mannich bases of 7-hydroxycoumarins are the products of the Mannich reaction, which is a classical, yet important electrophilic substitution reaction used as a synthetic tool in aromatic heterocyclic chemistry yielding a growing number of interesting compounds with potential in medicinal chemistry.…”

“…15 Concerning functionalized hydroxycoumarins, Mannich bases of 7-hydroxycoumarins are the products of the Mannich reaction, which is a classical, yet important electrophilic substitution reaction used as a synthetic tool in aromatic heterocyclic chemistry yielding a growing number of interesting compounds with potential in medicinal chemistry. 12,13 Some Mannich bases of hydroxycoumarins have been reported as potential treatment or to prevent Alzheimer's disease and to inhibit hepatitis C virus, 16 as well as their synthesis, 17 however their presence is scarce in the literature. Within this context, the interest of our research group on Mannich bases of hydroxycoumarins is driven, by the rationalization of the regioselectivity of the reaction through the hard and so acids and bases theory, 18 and by the study of both, the structural features of a third fused ring within the architecture of the coumarins, which is known to enhance the metabolic stability of the product as a potential pharmacophore and, 8,19 and the presence of two vicinal electron donor groups in the same uorophore which have been described as a relevant structural motif in the design of uorophores for several photophysical applications.…”