27172-99-2Relevant articles and documents
Reich et al.
, p. 5813 (1973)
Visible-Light-Mediated Heterocycle Functionalization via Geometrically Interrupted [2+2] Cycloaddition
Alegre-Requena, Juan V.,Mekereeya, Aroonroj,Paton, Robert S.,Popescu, Mihai V.,Smith, Martin D.
supporting information, p. 23020 - 23024 (2020/10/15)
The [2+2] photocycloaddition is the most valuable and intensively investigated photochemical process. Here we demonstrate that irradiation of N-acryloyl heterocycles with blue LED light (440 nm) in the presence of an IrIII complex leads to efficient and high yielding fused γ-lactam formation across a range of substituted heterocycles. Quantum calculations show that the reaction proceeds via cyclization in the triplet excited state to yield a 1,4-diradical; intersystem crossing leads preferentially to the closed shell singlet zwitterion. This is geometrically restricted from undergoing recombination to yield a cyclobutane by the planarity of the amide substituent. A prototropic shift leads to the observed bicyclic products in what can be viewed as an interrupted [2+2] cycloaddition.
The diazo route to diazonamide A: Studies on the tyrosine-derived fragment
Palmer, Francine N.,Lach, Franck,Poriel, Cyril,Pepper, Adrian G.,Bagley, Mark C.,Slawin, Alexandra M. Z.,Moody, Christopher J.
, p. 3805 - 3811 (2007/10/03)
Various approaches to the tyrosine-derived fragment of the marine secondary metabolite diazonamide A are described. Initial efforts were focused on the originally proposed structure of the natural product, and a feasibility study established that a model
