Absence of S[subscript N]1 Involvement in the Solvolysis of Secondary Alkyl Compounds

Autor/in	Murphy, Thomas J.
Titel	Absence of S[subscript N]1 Involvement in the Solvolysis of Secondary Alkyl Compounds
Quelle	In: Journal of Chemical Education, 86 (2009) 4, S.519-524 (6 Seiten)Infoseite zur Zeitschrift PDF als Volltext Verfügbarkeit
Sprache	englisch
Dokumenttyp	gedruckt; online; Zeitschriftenaufsatz
ISSN	0021-9584
Schlagwörter	Organic Chemistry; Textbooks; Kinetics; Laboratory Experiments; Molecular Structure; Undergraduate Study; Introductory Courses; Higher Education + Suchen Sie Ihr Suchwort? Organische Chemie; Textbook; Text book; Schulbuch; Lehrbuch; Kinetik; Laboratory work; Laborarbeit; Grundstudium; Einführungskurs; Hochschulbildung; Hochschulsystem; Hochschulwesen
Abstract	There are significant contradictions in undergraduate organic chemistry textbooks as to the mechanism of nucleophilic substitution reactions at saturated secondary carbons. Some texts say that only the S[subscript N]2 mechanism operates, others say that solvolysis reactions go entirely by the S[subscript N]1 mechanism, while most texts say that both mechanisms can be involved. This inconsistency greatly complicates the understanding of these reactions by students, and it leads to biases in testing. The root of this dilemma is traced to the initial studies by Hughes, Ingold, and co-workers in the 1930s. Despite discussing the difference between the kinetic order of a reaction and its molecularity, they often deferred to kinetic order in assigning a mechanism to these reactions. In 1969 Ingold considered it plausible that a first-order solvolysis reaction yielding a 100% inverted product was nonetheless going by an S[subscript N]1 mechanism and suggested that the solvolysis of secondary compounds went primarily by S[subscript N]1. The solvolysis of optically active 2-bromooctane should have resolved this issue, but major experimental difficulties confounded the results and lead to the continuing confusion. Based the results of Hughes, Ingold, and co-workers and significant additional evidence, it is concluded that all substitution reactions at saturated secondary carbons go exclusively via the S[subscript N]2 mechanism under usual conditions. (Contains 3 figures.) (As Provided).
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Erfasst von	ERIC (Education Resources Information Center), Washington, DC
Update	2017/4/10