ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Solvolyses of the 2,4-dinitrobenzoates of the cyclopropylcarbinol 1a, the cyclo-butanol 2a and the homoallylic alcohol 3a in buffered 70% aqueous dioxane lead to the same product mixture consisting of 78% cyclopropylcarbinol 1a and 22% homoallylic alcohol 3a. Approximately the same product mixture is optained when the homoallylic chloride 3b and the cyclopropylcarbinyl p-nitrobenzoate 1c are solvolyzed. A common cationic intermediate is indicated in these kinetically controlled rearrangement reactions. Under conditions of thermodynamic control only homoallylic products are formed.The 2,4-dinitrobenzoates 1d and 2d react 7.2 × 103 and 7.7 times, respectively, as fast as the homoallylic isomer 3d. Since the homoallylic chloride 3b reacts ca. 105 times as fast as its saturated analogue, 7-exo-bicyclo[3.2.1]octyl chloride 4, all three esters react with the enhanced rates which are characteristic of these structural types.The endo-cyclobutyl dinitrobenzoate 2d reacts more than 60 times as fast as its exo-isomer 6d. The rate difference is ascribed to a stereoelectronically more favorable orientation of the participating σ bonds in the puckered cyclobutane ring in the endo isomer 2d.
Additional Material:
4 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19730560323
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