| 1. |
- Bilgic, Mehmet B., et al.
(författare)
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An unusual zig-zag 2D copper(i) coordination polymer as an outstanding catalyst for azide–alkyne “click” chemistry at room temperature
- 2022
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Ingår i: Dalton Transactions. - : Royal Society of Chemistry (RSC). - 1477-9226 .- 1477-9234. ; 51:46, s. 17543-17546
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Tidskriftsartikel (refereegranskat)abstract
- A straightforward method for the synthesis of a two-dimensional (2D) new copper(I) coordination polymer, namely Cu(bzpdc), containing the ligand benzophenone 4,4′-dicarboxylate, and its effective use as catalyst for the azide–alkyne click chemistry at room temperature is reported. Zig-zag formation caused by cuprophilic interactions resulted in an unprecedented crystal structure with a very high copper content (45.5% by weight). The catalyst was stable up until 300 °C and tolerant to various solvents, including water. Cu(bzpdc) showed excellent catalytic activity for click reactions of several organic azides and alkynes having different functional groups at room temperature and is comparable to its homogenous analogues. The recyclability of Cu(bzpdc) was also tested and proven to be effective.
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| 2. |
- Kaya, Kerem, et al.
(författare)
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Nature-Inspired Depolymerization of Soda Lignin : Light-Induced Free Radical Promoted Cleavage of β-O-4 Bonds
- 2024
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Ingår i: Advanced Sustainable Systems. - 2366-7486. ; 8:3
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Tidskriftsartikel (refereegranskat)abstract
- The development of sustainable valorization methods for lignin is a challenging task because the vast majority of the reported studies involve either harsh conditions or expensive transition metal catalysts. Inspired by the sunlight degradation of lignin compounds, known as lignin yellowing, the use of a commercially available cheap organic photoinitiator, namely, phenacyl bromide (PAB) is reported here, for the efficient cleavage of lignin model compound 2-phenoxyacetophenone (2-PAP) and for the depolymerization of soda pulped lignin (SL) under UV-A irradiation and ambient conditions. Real-time NMR investigations of the photoreaction between 2-PAP and PAB shed light on the possible reaction mechanisms involving different radical species, HBr, and molecular oxygen. Interestingly, combined spectral, chromatographic, powder X-ray diffraction, and thermal studies of the photoreaction between PAB and SL indicate the formation of guaiacyl alcohol as the main product. The unprecedented performance of PAB is attributed to the excess generation of phenacyl radicals, the generation of photolabile brominated species, and HBr playing key roles in the cleavage of β-O-4 linkages. This work represents a new edge for sustainable lignin valorization under mild reaction conditions and offers the opportunity for large-scale production of valuable aromatics using technical lignins as feedstock.
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