Skeletal rearrangements of camphor are well-known, however, those involving camphorquinone, its sibling, are rare. We have found that the diol derived from allylated camphorquinone undergoes iodine or bromine mediated deep-seated skeletal rearrangement to provide an interesting tricyclic ring system. The iodo group in the rearranged product provided convenient leverage for further functionalization. For example, it was converted into an azide and the azide was subjected to copper(i) mediated Huisgen 1,3-dipolar cycloaddition with acetylenes to obtain a terpene-triazole conjugate.
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http://dx.doi.org/10.1039/d0ra09839f | DOI Listing |
Macromol Rapid Commun
August 2024
Université de Haute-Alsace, CNRS, IS2M UMR 7361, Mulhouse, F-68100, France.
The utilization of two-component systems comprising camphorquinone (CQ) and aromatic amines has become prevalent in the photopolymerization. However, there are still concerns about the safety of this CQ/amine system, mainly because of the toxicity associated with the leaching of aromatic amines. In light of these concerns, this study aims to develop novel coinitiator combinations featuring CQ and amines which cannot be leached out of materials, enabling free radical polymerization of representative dentalmethacrylate resins under blue light irradiation.
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August 2022
Dental and Biomaterials Science, College of Medical and Dental Science, Institute of Clinical Sciences, University of Birmingham, 5 Mill Pool Way, Edgbaston, Birmingham B5 7EG, UK. Electronic address:
Objective: Cyclic acetals such as are naturally occurring compounds capable of acting as co-initiators during free-radical polymerisation, and potentially serve to offer non-allergic and biologically less toxic alternatives to conventional (tertiary) amines. The current study aimed to evaluate the polymerisation efficiency and potential toxicity of cyclic acetals compared with conventional photoinitiator systems in photocurable dental resins.
Methods: Both, 1,3 benzodioxole (BZD) and piperonyl alcohol (PA) were used in 0.
RSC Adv
February 2021
Department of Chemistry, Pondicherry University Puducherry 605 014 India +91-9443264222.
Skeletal rearrangements of camphor are well-known, however, those involving camphorquinone, its sibling, are rare. We have found that the diol derived from allylated camphorquinone undergoes iodine or bromine mediated deep-seated skeletal rearrangement to provide an interesting tricyclic ring system. The iodo group in the rearranged product provided convenient leverage for further functionalization.
View Article and Find Full Text PDFDent Mater
March 2021
Université de Haute-Alsace, CNRS, IS2M UMR 7361, 68100 Mulhouse, France; Université de Strasbourg, 67000 Strasbourg, France. Electronic address:
Objectives: The two-component Camphorquinone (CQ)/aromatic amine system is well-established and clearly corresponds to the reference system used in all photopolymerizable dental adhesives and composites. However, this CQ/amine system still suffers from the presence of aromatic amines that can be referenced as toxic. Therefore, the aim of this work is to develop amine-free photoinitiating systems (PISs) for the polymerization of a representative dental methacrylate resins upon blue light irradiation.
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February 2020
Institut de Science des Matériaux de Mulhouse IS2M, UMR CNRS 7361, UHA, 15 Rue Jean Starcky, 68057 Mulhouse Cedex, France. Electronic address:
Objective: The aim of our study is to develop amine-free photoinitiating systems (PISs) for the polymerization of representative dental methacrylate resins under blue light irradiation. PISs based on camphorquinone (CQ)/sulfinate and CQ/sulfonate, eventually in combination with an iodonium salt, are proposed and compared to the well-established CQ/amine system. The polymerization performances of thick (1.
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