in organic synthesis and the pharmaceutical industry. The heterogeneous synthesis of nitrones with multifunctional catalysts is extremely attractive but rarely explored. Herein, we report ultrasmall platinum nanoclusters (PtNCs) encapsulated in amine‐functionalized Zr metal–organicframework (MOF), UiO‐66‐NH2 (Pt@UiO‐66‐NH2) as a multifunctional catalyst in the one‐pot tandem synthesis of nitrones
Efficient Synthesis of New 4-Arylideneimidazolin-5-ones Related to the GFP Chromophore by 2+3 Cyclocondensation of Arylideneimines with Imidate Ylides
作者:Janusz Kowalik、Anthony Baldridge、Laren Tolbert
DOI:10.1055/s-0029-1218796
日期:2010.7
A 2+3 condensation of a wide assortment of Schiff bases, prepared from aromatic aldehydes and primary amines, with methyl 2-(1-ethoxyethylideneamino)acetate allows convenient access to an extensive family of substituted 4-arylideneimidazolin-5-one analogues of the green fluorescent protein (GFP) chromophore. 4-arylideneimidazolin-5-one - azomethine ylide - Schiff bases - heterocycle - 2+3 cycloaddition
Steric and Electronic Effects in Capsule-Confined Green Fluorescent Protein Chromophores
作者:Anthony Baldridge、Shampa R. Samanta、Nithyanandhan Jayaraj、V. Ramamurthy、Laren M. Tolbert
DOI:10.1021/ja1094606
日期:2011.2.2
The turn-on of emission in fluorescent protein chromophores sequestered in an "octaacid" capsule is controlled by stereoelectronic effects described by a linear free energy relationship. The stereochemical effects are governed by both the positions and volumes of the aryl substituents, while the electronic effects, including ortho effects, can be treated with Hammett sigma parameters. The use of substituent volumes rather than A values reflects packing of the molecule within the confines of the capsule.
A Latent Reaction in a Model GFP Chromophore Revealed upon Confinement: Photohydroxylation of <i>ortho</i>-Halo Benzylidene-3-methylimidazolidiones via an Electrocylization Process
作者:Shampa R. Samanta、José P. Da Silva、Anthony Baldridge、Laren M. Tolbert、V. Ramamurthy
DOI:10.1021/ol5013058
日期:2014.6.20
Excited state behavior of halogensubstituted model GFP chromophores was investigated in an acetonitrile solution and in a confined environment provided by an octa acid capsule in water. Of the ortho, meta, and para halogensubstituted GFP chromophores only the ortho compounds gave a new product resulting from an unprecedented photosubstitution of halogens by the hydroxyl group. This unusual reaction