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Abstract The 1 : 2 reaction of the imidazole‐based dithiolate (2) with GeCl2 • dioxane in THF/TMEDA gives3, a TMEDA‐complexed dithiolene‐based germylene. Compound3is converted to monothiolate‐complexed (5) and N‐heterocyclic carbene‐complexed (7) germanium(II) dithiolene complexes via Lewis base ligand exchange. A bis‐dithiolene‐based germylene (8), involving a 3c–4e S‐Ge‐S bond, has also been synthesized through controlled hydrolysis of7. The bonding nature of3,5, and8was investigated by both experimental and theoretical methods.
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Investigations on the Synthesis, Reactivity, and Properties of Perfluoro‐α‐Benzo‐Fused BOPHY Fluorophores
Abstract The synthesis and reactivity of 3,8‐dibromo‐dodecafluoro‐benzo‐fused BOPHY2are reported, via SNAr with O‐, N‐ S‐ and C‐nucleophiles, and in Pd(0)‐catalyzed cross‐coupling reactions (Suzuki and Stille). The resulting perfluoro‐BOPHY derivatives were investigated for their reactivity in the presence of various nucleophiles. BOPHY3displays reversible color change and fluorescence quenching in the presence of bases (Et3N, DBU), whereas BOPHY7reacts preferentially at the α‐pyrrolic positions, and BOPHY8undergoes regioselective fluorine substitution in the presence of thiols. The structural and electronic features of the fluorinated BOPHYs were studied by TD‐DFT computations. In addition, their spectroscopic and cellular properties were investigated; BOPHY10shows the most red‐shifted absorption/emission (λmax659/699 nm) and7the highest fluorescence (Φf=0.95), while all compounds studied showed low cytotoxicity toward human HEp2 cells and were efficiently internalized.
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- Award ID(s):
- 2055190
- PAR ID:
- 10375249
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 28
- Issue:
- 35
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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