title: Measurement of heterogeneous reaction rates: three strategies for controlling mass transport and their application to indium-mediated allylations.
abstract: We describe three new strategies for determining heterogeneous reaction rates using photomicroscopy to measure the rate of retreat of metal surfaces: (i) spheres in a stirred solution, (ii) microscopic powder in an unstirred solution, and (iii) spheres on a rotating shaft. The strategies are applied to indium-mediated allylation (IMA), which is a powerful tool for synthetic chemists because of its stereoselectivity, broad applicability, and high yields. The rate-limiting step of IMA, reaction of allyl halides at indium metal surfaces, is shown to be fast, with a minimum value of the heterogeneous rate constant of 1 × 10(-2) cm/s, an order of magnitude faster than the previously determined minimum value. The strategies described here can be applied to any reaction in which the surface is retreating or advancing, thereby broadening the applicability of photomicroscopy to measuring heterogeneous reaction kinetics.
authors: Department of Chemistry, Hobart and William Smith Colleges, Geneva, New York 14456, USA.
authors: Isabel A
authors: IA
authors: Olson
authors: Wendi A
authors: WA
authors: Bacon
authors: Yessica Y
authors: YY
authors: Baez Sosa
authors: Katherine M
authors: KM
authors: Delaney
authors: Salvador A
authors: SA
authors: Forte
authors: Michael A
authors: MA
authors: Guglielmo
authors: Alexa N
authors: AN
authors: Hill
authors: Katrina H
authors: KH
authors: Kiesow
authors: Rachel E
authors: RE
authors: Langenbacher
authors: Yuhan
authors: Y
authors: Xun
authors: Ryan O
authors: RO
authors: Young
authors: Walter J
authors: WJ
authors: Bowyer
mesh_terms: D000498:Allyl Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D006846:Hydrocarbons, Halogenated / Q000737:chemistry; D007204:Indium / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D010316:Particle Size; D010784:Photomicrography; D012996:Solutions; D013237:Stereoisomerism; D013499:Surface Properties
chemical_list: D000498:Allyl Compounds; D006846:Hydrocarbons, Halogenated; D009942:Organometallic Compounds; D012996:Solutions; D007204:Indium