No abstract

Organoselenium compounds constitute an important class of substances with applications in the biological, medicinal and material sciences as well as in modern organic synthesis, attracting considerable attention from the scientific community. Therefore, the construction of the C−Se bond via facile, efficient and sustainable strategies to access complex scaffolds from simple substrates are an appealing and hot topic. Visible light can be regarded as an alternative source of energy and is associated with environmentally‐friendly processes. Recently, the use of visible‐light mediated seleno‐functionalization has emerged as an ideal and powerful route to obtain high‐value selenylated products, with diminished cost and waste. This approach, involving photo‐excited substrates/catalyst and single‐electron transfer (SET) between substrates in the presence of visible light has been successfully used in the versatile and direct insertion of organoselenium moieties in activated and unactivated C(sp3)−H, C(sp2)−H, C(sp)−H bonds as well as C−heteroatom bonds. In most cases, ease of operation and accessibility of the light source (LEDs or commercial CFL bulbs) makes this approach more attractive and sustainable than the traditional strategies.

Functionalization of double bonds with arylselenium groups found in the literature, commonly uses high temperatures in the presence of metal catalysts, reducing agents or other additives. In this context, this work presents a series of bis‐arylselanyl olefins synthesized by photoinduced reaction without heating or additives. Since the absorption range of the diselenide comprises the UV/Visible region of spectra, a mixture of arylacetylene and diaryl diselenide in dichloromethane was irradiated with white light from compact (household) fluorescent lamp. The optimized procedure allows preparation of E‐olefins due to radical addition followed by photoisomerization with low cost and low environmental impact.

No abstract

No abstract

No abstract

No abstract

A series of new organochalcogen derivatives of benzimidazo[1,2-a]quinolines were synthesized. Both sulfur and selenium derivatives presented similar photophysical properties with absorption in the UV region and fluorescence emission in the violet-blue.