Publications by authors named "Dylan J Shields"

Irradiation of -methoxyazidobutyrophenone () in methanol yielded 2-(4-methoxyphenyl)-1-pyrroline () and several other photoproducts. However, in the presence of tris(trimethylsilyl)silane (TTMSS), is formed selectively. Transient absorption and ESR spectroscopy verify that the irradiation of forms triplet alkylnitrene through intramolecular energy transfer from the triplet ketone (T).

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Well-defined dinuclear silver(I) complexes have been targeted for applications in catalysis and materials chemistry, and the effect of close silver-silver interactions on electronic structure remains an area of active inquiry. In this study, we describe the synthesis, structure, and photophysical properties of dimeric silver complexes featuring a redox-active naphthyridine diimine ligand. Unusually for silver(I), these complexes display absorption features in the visible region due to metal-metal to ligand charge transfer (MMLCT) transitions, which arise from the combination of close silver-silver interactions and low-lying ligand π* orbitals.

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When exposed to UV light, single crystals of the vinyl azides 3-azido-1-phenylpropenone (), 3-azido-1-(4-methoxyphenyl)propenone (), and 3-azido-1-(4-chlorophenyl)propenone () exhibit dramatic mechanical effects by cracking or bending with the release of N. Mechanistic studies using laser flash photolysis, supported by quantum mechanical calculations, show that each of the vinyl azides degrades through a vinylnitrene intermediate. However, despite having very similar crystal packing motifs, the three compounds exhibit distinct photomechanical responses in bulk crystals.

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Article Synopsis
  • The photolysis of 2,3-diazidonaphthalene-1,4-dione in methyltetrahydrofuran produces vinylnitrene, which has been confirmed using electron paramagnetic resonance spectroscopy.
  • The zfs parameters indicate strong 1,3-biradical character, with specific values for and .
  • Additionally, irradiating vinylnitrene leads to the formation of alkylnitrene, which shows zfs parameters characteristic of cycloalkylnitrene when tested in argon matrices.
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