Juan C. Scaiano

Bio: Juan C. Scaiano is an academic researcher from University of Ottawa. The author has contributed to research in topics: Flash photolysis & Triplet state. The author has an hindex of 61, co-authored 407 publications receiving 15301 citations. Previous affiliations of Juan C. Scaiano include National University of Río Cuarto & Linköping University.

Modern Molecular Photochemistry of Organic Molecules

Abstract: 1. Molecular Photochemistry of Organic Compounds: An Overview 2. Electronic, Vibrational, and Spin Configurations of Electronically Excited States 3. Transitions between States: Photophysical Processes 4. Radiative Transitions between Electronic States 5. Photophysical Radiationless Transitions 6. A Theory of Molecular Organic Photochemistyr 7. Energy Transfer and Electron Transfer 8. Mechanistic Organic Photochemistry 9. Photochemistry of Carbonyl Compounds 10. Photochemistry of Olefins 11. Photochemistry of Enones and Dienones 12. Photochemistry of Aromatic Molecules 13. Supramolecular Organic Photochemistry 14. Molecular Oxygen and Organic Photochemistry 15. A Generalization of the Photochemistry of Organic Molecules Index

Principles of Molecular Photochemistry: An Introduction

Abstract: Preface Molecular Photochemistry of Organic Compounds: An Overview Electronic, Vibrational, and Spin Configurations of Electronically Excited States Transitions Between States: Photophysical Processes Radiative Transitions Between Electronic States Photophysical Radiationless Transitions A Theory of Molecular Organic Photochemistry Energy Transfer and Electron Transfer Index

Rate constants for the reactions of free radicals with oxygen in solution

Abstract: The kinetics of the rections of several free radicals with oxygen have been examined in solution at 300 K using laser flash photolysis techniques. The reactions of resonance-stabilized radicals are only slightly slower than those of nonstabilized radicals: for example, for tert-butyl (in cyclohexane), 4.93 x 10/sup 9/; benzyl, 2.36 x 10/sup 9/ (in cyclohexane); cyclohexadienyl (in benzene), 1.64 x 10/sup 9/ M/sup -1/ s/sup -1/. The reaction of butyl-tin (n-Bu/sub 3/Sn.) radicals is unusually fast (7.5 x 10/sup 9/ M/sup -1/ s/sup -1/), a fact that has been tentatively attributed to a relaxation of spin selection rules due to heavy atom effects. 1 table.

Light emitting diode irradiation can control the morphology and optical properties of silver nanoparticles.

Abstract: A facile method for the preparation of silver nanoparticles (AgNPs) of various sizes and morphologies, including dodecahedra, nanorods, and nanoplates, has been discovered. By choosing the desired optical properties (absorption maximum) and irradiating spherical AgNP seeds with a selected light emitting diode, we achieve control over the size, morphology, and optical properties. The properties of AgNPs are intrinsically dependent on the size and shape of the particles, which can be readily controlled with the strategies reported here. Literature methods for the synthesis of anisotropic AgNPs require complex solutions containing seed nanoparticles with specific twinning defects, and a variety of specific stabilizing ligands direct the growth of the seeds but limit the versatility of the particles. In general, these thermal routes to anisotropic AgNPs give particles with high polydispersity, limiting their applications in single molecule spectroscopy and surface plasmon resonance spectroscopy. We describe a single photochemical method for preparation of AgNPs with predictable and controllable size and morphology that are produced from a single source of photochemically grown AgNP seeds stabilized only by sodium citrate. We also describe a common mechanism for the formation of the various types of AgNPs.

The Chemistry behind Antioxidant Capacity Assays

Abstract: This review summarizes the multifaceted aspects of antioxidants and the basic kinetic models of inhibited autoxidation and analyzes the chemical principles of antioxidant capacity assays. Depending upon the reactions involved, these assays can roughly be classified into two types: assays based on hydrogen atom transfer (HAT) reactions and assays based on electron transfer (ET). The majority of HAT-based assays apply a competitive reaction scheme, in which antioxidant and substrate compete for thermally generated peroxyl radicals through the decomposition of azo compounds. These assays include inhibition of induced low-density lipoprotein autoxidation, oxygen radical absorbance capacity (ORAC), total radical trapping antioxidant parameter (TRAP), and crocin bleaching assays. ET-based assays measure the capacity of an antioxidant in the reduction of an oxidant, which changes color when reduced. The degree of color change is correlated with the sample's antioxidant concentrations. ET-based assays include th...

Organic Photoredox Catalysis

Abstract: In this review, we highlight the use of organic photoredox catalysts in a myriad of synthetic transformations with a range of applications. This overview is arranged by catalyst class where the photophysics and electrochemical characteristics of each is discussed to underscore the differences and advantages to each type of single electron redox agent. We highlight both net reductive and oxidative as well as redox neutral transformations that can be accomplished using purely organic photoredox-active catalysts. An overview of the basic photophysics and electron transfer theory is presented in order to provide a comprehensive guide for employing this class of catalysts in photoredox manifolds.

Fluorine in pharmaceutical industry: fluorine-containing drugs introduced to the market in the last decade (2001-2011).

Abstract: Introduced to the Market in the Last Decade (2001−2011) Jiang Wang,† María Sańchez-Rosello,́‡,§ Jose ́ Luis Aceña, Carlos del Pozo,‡ Alexander E. Sorochinsky, Santos Fustero,*,‡,§ Vadim A. Soloshonok,* and Hong Liu*,† †Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China ‡Department of Organic Chemistry, Faculty of Pharmacy, University of Valencia, Av. Vicente Andreś Estelleś, 46100 Burjassot, Valencia, Spain Laboratorio de Molećulas Orgańicas, Centro de Investigacioń Príncipe Felipe, C/ Eduardo Primo Yuf́era 3, 46012 Valencia, Spain Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizab́al 3, 20018 San Sebastian, Spain IKERBASQUE, Basque Foundation for Science, Alameda Urquijo, 36-5 Plaza Bizkaia, 48011 Bilbao, Spain Institute of Bioorganic Chemistry and Petrochemistry, National Academy of Sciences of Ukraine, Murmanska Street 1, 02660 Kyiv-94, Ukraine