1
|
Cink RB, Zhou Y, Du L, Rahman MS, Phillips DL, Simpson MC, Seed AJ, Sampson P, Brasch NE. Mechanistic Insights into Rapid Generation of Nitroxyl from a Photocaged N-Hydroxysulfonamide Incorporating the (6-Hydroxynaphthalen-2-yl)methyl Chromophore. J Org Chem 2021; 86:8056-8068. [PMID: 34107217 DOI: 10.1021/acs.joc.1c00457] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
HNO is a highly reactive molecule that shows promise in treating heart failure. Molecules that rapidly release HNO with precise spatial and temporal control are needed to investigate the biology of this signaling molecule. (Hydroxynaphthalen-2-yl)methyl-photocaged N-hydroxysulfonamides are a new class of photoactive HNO generators. Recently, it was shown that a (6-hydroxynaphthalen-2-yl)methyl (6,2-HNM)-photocaged derivative of N-hydroxysulfonamide incorporating the trifluoromethanesulfonamidoxy group (1) quantitatively generates HNO. Mechanistic studies have now been carried out on this system and reveal that the ground state protonation state plays a key role in whether concerted heterolytic C-O/N-S bond cleavage to release HNO occurs versus undesired O-N bond cleavage. N-Deprotonation of 1 can be achieved by adding an aqueous buffer or a carboxylate salt to an aprotic solvent. Evidence is presented for C-O/N-S bond heterolysis occurring directly from the singlet excited state of the N-deprotonated parent molecule on the picosecond time scale, using femtosecond time-resolved transient absorption spectroscopy, to give a carbocation and 1NO-. This is consistent with the observation of significant fluorescence quenching when HNO is generated. The carbocation intermediate reacts rapidly with nucleophiles including water, MeOH, or even (H)NO in the absence of a molecule that reacts rapidly with (H)NO to give an oxime.
Collapse
Affiliation(s)
- Ruth B Cink
- School of Science, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand.,The Photon Factory, School of Chemical Sciences and Department of Physics, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.,The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6012, New Zealand.,The Dodd-Walls Centre for Quantum and Photonic Technologies, Dunedin 9054, New Zealand
| | - Yang Zhou
- Department of Chemistry and Biochemistry, Kent State University, Kent, Ohio 44242, United States
| | - Lili Du
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong SAR 99077, P. R. China
| | - Mohammad S Rahman
- Department of Chemistry and Biochemistry, Kent State University, Kent, Ohio 44242, United States
| | - David Lee Phillips
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong SAR 99077, P. R. China
| | - M Cather Simpson
- The Photon Factory, School of Chemical Sciences and Department of Physics, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.,The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6012, New Zealand.,The Dodd-Walls Centre for Quantum and Photonic Technologies, Dunedin 9054, New Zealand
| | - Alexander J Seed
- Department of Chemistry and Biochemistry, Kent State University, Kent, Ohio 44242, United States
| | - Paul Sampson
- Department of Chemistry and Biochemistry, Kent State University, Kent, Ohio 44242, United States
| | - Nicola E Brasch
- School of Science, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand.,The Dodd-Walls Centre for Quantum and Photonic Technologies, Dunedin 9054, New Zealand.,The Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| |
Collapse
|
2
|
López-Carballeira D, Casanova D, Ruipérez F. Theoretical design of conjugated diradicaloids as singlet fission sensitizers: quinones and methylene derivatives. Phys Chem Chem Phys 2017; 19:30227-30238. [DOI: 10.1039/c7cp05120d] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
New conjugated diradicaloids as potential candidates for singlet fission sensitizers.
Collapse
Affiliation(s)
- Diego López-Carballeira
- POLYMAT, University of the Basque Country UPV/EHU
- Joxe Mari Korta Center
- Donostia-San Sebastián
- Spain
| | - David Casanova
- Donostia International Physics Center (DIPC) and Kimika Fakultatea
- Euskal Herriko Unibertsitatea (UPV/EHU)
- 20080 Donostia
- Spain
- IKERBASQUE
| | - Fernando Ruipérez
- POLYMAT, University of the Basque Country UPV/EHU
- Joxe Mari Korta Center
- Donostia-San Sebastián
- Spain
| |
Collapse
|