Thermolysis of Alkyl Sulfoxides and Derivatives: A Comparison of Experiment and Theory

Autor:	Jerry W. Cubbage, Ryan D. McCulla, Yushen Guo, William S. Jenks
Rok vydání:	2001
Předmět:	chemistry.chemical_classification Addition reaction Organic Chemistry Enthalpy Substituent Sulfoxide Medicinal chemistry Elimination reaction chemistry.chemical_compound chemistry Nucleophile Acetylene Organic chemistry Alkyl
Zdroj:	The Journal of Organic Chemistry. 66:8722-8736
ISSN:	1520-6904 0022-3263
Popis:	Gas-phase activation data were obtained for model sulfoxide elimination reactions. The activation enthalpy for methyl 3-phenylpropyl sulfoxide is 32.9 +/- 0.9 kcal/mol. Elimination by methyl vinyl sulfoxide to form acetylene has an enthalpic barrier of 41.6 +/- 0.8 kcal/mol and that of 3-phenylpropyl methanesulfinate to form hydrocinnamaldehyde is 34.6 +/- 0.6 kcal/mol. Calculations at the MP2/6-311+G(3df,2p)//MP2/6-31G(d,p) level for simplified models of these reactions provide barriers of 32.3, 40.3, and 32.7 kcal/mol, respectively. A series of other compounds are examined computationally, and it is shown that the substituent effects on the sulfoxide elimination reaction are much more straightforward to interpret if DeltaH data are available in addition to the usually determined DeltaH++. The activation enthalpy of the reverse addition reaction is also subject to structural variation and can usually be rationalized on the basis of nucleophilicity of the sulfur or polarity matching between the sulfenic acid and olefin derivative.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::3de0da611b89ef2d8d8a51d013e59fc2 https://doi.org/10.1021/jo0160625 Zobrazit plný text záznamu