Water can accelerate a variety of organic reactions far beyond the rates observed in classical organic solvents. However, using pure water as a solvent introduces solubility constraints that have limited the applicability of efficient photochemistry in particular. We report here the formation of aggregates between pairs of arenes, heteroarenes, enamines, or esters with different electron affinities in an aqueous medium, leading to an oil-water phase boundary through substrate melting point depression. The active hydrogen atoms in the reactants engage in hydrogen bonds with water, thereby accelerating photochemical reactions. This methodology realizes appealingly simple conditions for aqueous coupling reactions of complex solid molecules, including complex drug molecules that are poorly soluble in water.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1126/science.adl3092 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Decoding the physicochemical basis of resurrection: the journey of lichen Flavoparmelia caperata through prolonged water scarcity to full rehydration.
BMC Plant Biol
December 2024
Plant Bioenergetics and Biotechnology Laboratory, Department of Botany, Mohanlal Sukhadia University, Udaipur, Rajasthan, India.
Desiccation tolerance is a complex phenomenon observed in the lichen Flavoparmelia ceparata. To understand the reactivation process of desiccated thalli, completely dried samples were rehydrated. The rehydration process of this lichen occurs in two phases.
View Article and Find Full Text PDFNitrate-Photolysis Shortens the Lifetimes of Brown Carbon Tracers from Biomass Burning.
Environ Sci Technol
December 2024
State Ecology and Environment Scientific Observation and Research Station for the Yangtze River Delta at Dianshan Lake, Shanghai Environmental Monitoring Center, Shanghai 200030, China.
Biomass burning is an important source of brown carbon (BrC) aerosols, which influence climate by affecting the Earth's radiative balance. However, the transformation pathways of BrC chromophores, especially in the presence of photochemically active species, such as nitrate, are not well understood. In this study, the nitrate-mediated aqueous-phase photooxidation of three typical BrC chromophores from biomass burning was investigated, including 4-nitrocatechol, 3-nitrosalicylic acid, and 3,4-dinitrophenol.
View Article and Find Full Text PDFAssembly of Pyrenes through a Quadruple Photochemical Cascade: Blocking Groups Allow Diversion from the Double Mallory Path to Photocyclization at the Bay Region.
J Am Chem Soc
December 2024
Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States.
We present a six-step cascade that converts 1,3-distyrylbenzenes (-stilbenes) into nonsymmetric pyrenes in 40-60% yields. This sequence merges photochemical steps, ,-alkene isomerization, a 6π photochemical electrocyclization (Mallory photocyclization); the new bay region cyclization, with two radical iodine-mediated aromatization steps; and an optional aryl migration. This work illustrates how the inherent challenges of engineering excited state reactivity can be addressed by logical design.
View Article and Find Full Text PDFEnhanced oxidative potential and SO heterogeneous oxidation on candle soot after photochemical aging: Influencing mechanisms of different irradiation wavelengths.
Environ Pollut
December 2024
School of Environmental Science and Engineering, Changzhou University, Changzhou, 213164, China; Key Laboratory of Advanced Plasma Catalysis Engineering for China Petrochemical Industry, Jiangsu, 213164, China. Electronic address:
Photochemistry plays a significant role in the atmospheric aging processes of soot. However, the physicochemical properties and changes in environmental and health effects of soot particles from sacrificial sources after photochemical aging remain unclear. The reaction mechanisms of soot under different irradiation wavelengths require further investigation.
View Article and Find Full Text PDFVisible-Light-Induced -Quinone Methides Formation in Situ Using -Alkylarenols as Precursors for Tandem [4 + 2] Cycloaddition Reaction.
Org Lett
December 2024
Key Laboratory of Photochemical Conversion and Optoelectronic Materials, New Cornerstone Science Laboratory, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences, Beijing 100190, P. R. China.
Reported herein is the generation of -quinone methides (-QMs) via metal-free visible-light-induced oxidation of -alkylarenols, as well as their subsequent reaction with olefins to afford chromans in good to excellent yields (up to 91%). The key is the selective activation of the benzylic C(sp)-H bond of -alkylarenols via single electron transfer (SET) and the formation of -QMs via hydrogen atom transfer (HAT).
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!