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![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Disassembly kinetics of quinone-methide-based self-immolative spacers that contain aromatic nitrogen heterocycles
Ahmed Alouane1, Raphaël Labruère, Katherine J Silvestre
1Institut Curie, Centre de Recherche, 26 rue d'Ulm, Paris F-75248 (France), Fax: (+33) 1-56-24-66-31; CNRS, UMR 176, 26 rue d'Ulm, Paris F-75248 (France); Ecole Normale Supérieure, Département de Chimie, UMR CNRS-ENS-UPMC 8640 PASTEUR, 24 rue Lhomond, 75231 Paris (France).
Abstract:
We prepared several pyridine- and pyrimidine-based self-immolative spacer groups to evaluate the significance of the resonance energy of the spacer aromatic ring on the kinetics of 1,4- and 1,6-elimination reactions, which govern spacer disassembly. Subsequently, we relied on a photoactivation procedure to accurately analyze the disassembly kinetics. Beyond providing new results that are relevant for deriving quantitative structure-property relationships, herein, we demonstrate that pH value can be used as an efficient parameter to finely control the disassembly time of a self-immolative spacer after an initial activation.
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