Namboothiri, INN and Balasubrahmanyam, SN (1993) On The Temperature-Dependence of Regioselectivity in the Amination of Bromobenzotropones. In: Indian Journal of Chemistry - Section B: Organic and Medicinal Chemistry, 32 (10). pp. 1029-1034.Full text not available from this repository.
The ipso/cine ratio in the amination of 5-bromo-2,3-benzo- or 2-bromo-4,5-benzotropone shows a dependence upon the temperature at which the reaction is conducted, changing in favour of the ipso-product when the temperature is maintained high, ruling out an aryne-type mechanism. A comparison of independent mechanisms envisaged for the formation of the two isomeric products suggests a two-part reason: (i) at a higher reaction temperature, C-protonation, a step necessary for the formation of the cine-product, could be retarded when a direct internal mode is interfered with by a less efficient external one, and (ii) reketonisation by elimination of bromide, needed to form the ipso-product, is likely to have a high temperature coefficient enabling the rate of its formation to overtake that of the cine-product.
|Item Type:||Journal Article|
|Additional Information:||Copyright of this article belongs to National Institute of Science Communication and Information Resources.|
|Department/Centre:||Division of Chemical Sciences > Organic Chemistry|
|Date Deposited:||18 Feb 2011 07:38|
|Last Modified:||18 Feb 2011 07:38|
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