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Title: Reactions of small organic molecules on silver(110)

The interaction of two pairs of molecules (1) acetone (CH[sub 3])[sub 2]C=O and isobutylene (CH[sub 3])[sub 2] C=CH[sub 2] and (2) 1,2-propanediol CH[sub 3] CH (OH)CH[sub 2]OH and 1,3-propanediol HOCH[sub 2]CH[sub 2]CH[sub 2]OH with clean and oxygen-activated Ag(110) has been explored to investigate the effects of molecular structure on reactivity. Experimental techniques employed include temperature programmed reaction spectroscopy, isotopic labelling, surface displacement reactions, and electron energy loss spectroscopy. Acetone and isobutylene were studied to explore the relative importance of C=O and C=C bonds in governing the reactivity of structurally similar compounds. Nucleophilic attack by oxygen at the electron-deficient carbonyl carbon in acetone results in reversible formation of the metallacycle (CH[sub 3])[sub 2]COO[sub (a)] at 110 K. Upon heating C-H bond activation by O[sub (a)] occurs near 215 K to yield acetone enolate CH[sub 2]=C(CH[sub 3])O[sub (a)] and evolve H[sub 2]O[sub (g)]. Atomic oxygen activates methyl C-H bonds in isobutylene via an acid-base mechanism. Although the major products are CO[sub 2(g)] and H[sub 2]O[sub (g)], a small amount of (CH[sub 3])[sub 2]C=CH[sub 2(g)] evolves near 310 K. Evidence for the formation of [pi]-2-methylallyl CH[sub 3]C(CH[sub 2])[sub 2(a)] and trimethylenementhane C(CH[sub 2])[sub 3(a)] is presented. The reaction of 1,2-propanediol CH[sub 3] CH(OH)CH[submore » 2] OH with oxygen-activated Ag(110) has been compared with that of 1,3-propanediol HOCH[sub 2]CH[sub 2]CH[sub 2]OH to evaluate the effects of varying the position of O-H bonds in both diols to produce the corresponding dialkoxides.« less
Authors:
Publication Date:
OSTI Identifier:
6980999
Resource Type:
Miscellaneous
Resource Relation:
Other Information: Thesis (Ph.D.)
Publisher:
Stanford, CA (United States); Stanford Univ.
Research Org:
Stanford Univ., CA (United States)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 2-METHYLPROPENE; CHEMICAL REACTIONS; ACETONE; GLYCOLS; SILVER; ACTIVATION ENERGY; CHEMICAL BONDS; CHEMICAL REACTION KINETICS; MOLECULAR STRUCTURE; TEMPERATURE DEPENDENCE; ALCOHOLS; ALKENES; ELEMENTS; ENERGY; HYDROCARBONS; HYDROXY COMPOUNDS; KETONES; KINETICS; METALS; ORGANIC COMPOUNDS; REACTION KINETICS; TRANSITION ELEMENTS 400201* -- Chemical & Physicochemical Properties