A series of [2+2]-photocycloadditions of 1,4-naphthoquinone with various alkenes and diphenylacetylene were investigated under batch and continuous-flow conditions. Acetone-sensitization furnished the corresponding photoadducts in good to excellent yields and purities. Compared to batch operations that demanded exhaustive irradiation times of 10-13 h, the flow process generally gave superior conversions and subsequently yields with a residence time of just 60 min. The structures of several photoaddition products were further determined by crystal structure analysis.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.3390/molecules29245920 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
[2+2]-Photocycloadditions of 1,4-Naphthoquinone Under Batch and Continuous-Flow Conditions.
Molecules
December 2024
College of Science and Engineering, James Cook University, Townsville, QLD 4811, Australia.
A series of [2+2]-photocycloadditions of 1,4-naphthoquinone with various alkenes and diphenylacetylene were investigated under batch and continuous-flow conditions. Acetone-sensitization furnished the corresponding photoadducts in good to excellent yields and purities. Compared to batch operations that demanded exhaustive irradiation times of 10-13 h, the flow process generally gave superior conversions and subsequently yields with a residence time of just 60 min.
View Article and Find Full Text PDFSalts of trans-3-Styryl Pyridine: The Effect of N-Quaternization on Solid-State Photoreactivity, and Photochemical Crystal Melting.
Chem Asian J
December 2024
Department of Chemistry, College of Engineering and Technology, SRM Institute of Science and Technology, 603203, Kattankulathur, Tamil Nadu, India.
Investigating solid-state photoreactivity, driven by crystal packing, has been a major enduring research theme in Crystal Engineering. Trans-3-styryl pyridine (3-StPy), an unsymmetric olefin, is photo-stable. However, when converted to a series of salts, they exhibited solid-state photoreactivity under UV irradiation.
View Article and Find Full Text PDFMetal-free [2+2]-photocycloaddition of unactivated alkenes enabled by continuous flow processing.
Chem Commun (Camb)
December 2024
School of Chemistry, University College Dublin, Science Centre South, Dublin 4, Ireland.
We report a continuous flow approach generating bicyclic cyclobutanes from unactivated alkenes in a metal-free manner that is inspired by the Kochi-Salomon reaction. A filtered Hg-lamp in combination with a simple flow set-up and acetone as UV light-absorbing co-solvent are crucial for this method thus showcasing attractive features for further exploitations.
View Article and Find Full Text PDFRegio- and diastereoselective synthesis of cyclobutylated phenothiazines [2 + 2] photocycloaddition: demonstrating wavelength-gated cycloreversion inside live cells.
Chem Sci
January 2025
Department of Chemistry, Indian Institute of Science Education and Research (IISER) Bhopal Academic Building - 2, Bhopal By-pass Road, Bhauri Bhopal-462066 India
Herein, we unveiled a regio- and diastereoselective synthesis of cyclobutylated phenothiazines, a unique class of structural congeners of phenothiazines visible-light-irradiated intermolecular [2 + 2]-cycloaddition reaction, from readily available naphthoquinones, 2-aminothiophenols, and styrenes, either in a two-step or three-component coupling process. By varying substitutions in all three coupling partners, a library of cyclobutylated phenothiazines, including late-stage derivatization with five commercial drugs, has been realized with up to 97% isolated yield. In contrast to the reported pathways, the developed [2 + 2]-photocycloaddition seems to proceed a 'photoinduced-electron-transfer' (PET) mechanism, which is well corroborated with the experimental observations, Rehm-Weller equation, and computation studies.
View Article and Find Full Text PDFPhotoredox-Catalyzed Decarboxylation of Oxetane-2-Carboxylic Acids Initiated by Oxidation of DIPEA.
Angew Chem Int Ed Engl
December 2024
U-M: University of Michigan, Department of Chemistry, 930 North University, 48109, Ann Arbor, UNITED STATES OF AMERICA.
Oxetanes are valuable motifs in medicinal chemistry applications, with demonstrated potential to serve as bioisosteres for an array of functional groups. Through the visible-light-mediated photoredox hydrodecarboxylation of 2-aryl oxetane 2-carboxylic acids this work enables access to the products of a [2+2]-photocycloaddition between alkenes and aryl aldehydes without the challenges associated with a traditional UV-light-mediated Paternò-Büchi reaction. Investigation into the hydrodecarboxylation mechanism reveals substrate-dependent modes of initiation under the conditions reported herein.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!