-S1 - Supporting Information Gold-Nanoparticle-Embedded Poly(N-isopropylacrylamide) Microparticles for Selective Quasi-Homogeneous Catalytic Homocoupling Reactions Pascal N. Eyimegwu, Jemima A. Lartey, and Jun-Hyun Kim* Department of Chemistry, Illinois State University, 4160 Campus Box, Normal, IL 61790- 4160, U.S.A. E-mail: jkim5@ilstu.edu Materials Ammonium persulfate (APS), N,N'-methylene-bis-acrylamide (BIS), nitric acid, hydrochloric acid, trisodium citrate, potassium carbonate (K2CO3), sodium carbonate (Na2CO3), trisodium phosphate (Na3PO4), potassium hydroxide (KOH), sodium hydroxide (NaOH), tripotassium phosphate (K3PO4), phenylboronic acid, biphenyl, phenol, 2-methylphenylboronic acid, 4- methylphenylboronic acid, 4-hydroxylphenylboronic acid, 4-methoxyphenylboronic acid, 4- carboxyphenylboronic acid, 2,2'-dimethylbiphenyl, 4,4'-dimethylbiphenyl, 4,4'- dihydroxybiphenyl, 4,4'-biphenyldicarboxylic acid, methanol, ethanol, propanol, isopropanol, benzene, butanol, acetonitrile, t-butanol, toluene, dichloromethane, chloroform, carbon tetrachloride, dioxane, ethyl acetate, acetone, tetrahydrofuran, dimethylforamide, dimethyl sulfoxide, octane, pyridine, triethylamine, and diethylamine, and hydrogen tetrachloroaurate trihydrate (HAuCl4∙3H2O) were obtained from Fisher Scientific. 4,4'-dimethoxybiphenyl was obtained from Aldrich; all of the chemicals were used without purification. N- isopropylacrylamide (NIPAM, Aldrich) was recrystallized in hexanes and dried under vacuum prior to use. The water used in all reactions was purified to a resistance of 18 MΩ (Nanopure water system; Barnstead/Thermolyne) and filtered through a 0.2 μm membrane. Glassware was cleaned with an aqua regia solution or a base bath, and then rinsed with water. Characterization The overall structural features of the composite particles were examined by the combination of scanning electron microscope (SEM), transmission electron microscope (TEM), and dynamic light scattering (DLS). The diameter distribution and morphology were characterized by SEM (FEI-Quanta 450 operating at a voltage of 20 kV) and TEM (Hitachi H8100 operating at a voltage of 200 kV). Scanning transmission electron microscopy (STEM) images and energy dispersive X-ray (EDX) maps/spectra were collected using a BioCryo Hitachi HD-2300A Dual EDS S/TEM at 200 keV (Hitachi High-Technologies Corp.). All particle samples for the SEM analysis were coated with a gold film using a sputter coater (DESKII) after completely drying them on silicon wafers at room temperature. The particle samples for the TEM analysis were deposited on 300 mesh carbon-coated copper grids. The size of the PNIPAM microparticles and embedded AuNPs was estimated from the collected images using ImageJ software (v1.45s, National Institute of Health) by counting more than 250 nanoparticles. The hydrodynamic diameter/polydispersity and zeta potential of the particles were examined with a dynamic light