DFT calculations have been carried out in order to rationalize and predict the ring-opening regioselectivity of substituted cyclopropenes in the presence of gold(I) catalysts. It has been shown that the regioselectivity of these ring-opening processes is driven by the relative π-donor ability of the substituents on the cyclopropene double bond (C1 and C2). A stronger π--donor substituent at C2 favors Au(I)-induced polarization of the double bond toward C1, resulting in preferential breaking of the C1-C3 bond. An excellent correlation between ΔE‡ and the difference in the C1-C2 p(π-) orbital population was observed for a broad range of substituents, providing a useful predictive model for gold-induced cyclopropene ring-opening. Furthermore, it was found that the stability of the resulting gold-stabilized allyl-cation intermediates do not follow the same trend as the ring-opening reaction energies. Generally, the more facile ring-opening process led to the less thermodynamically stable intermediate, which lacked stabilization of the carbocation by a π--donor in the α-position.

Item Type:	Refereed Article
Keywords:	cyclopropenes
Research Division:	Chemical Sciences
Research Group:	Other Chemical Sciences
Research Field:	Organometallic Chemistry
Objective Division:	Expanding Knowledge
Objective Group:	Expanding Knowledge
Objective Field:	Expanding Knowledge in the Chemical Sciences
UTAS Author:	Ariafard, A (Associate Professor Alireza Ariafard)
ID Code:	89197
Year Published:	2013
Web of Science® Times Cited:	11
Deposited By:	Chemistry
Deposited On:	2014-02-26
Last Modified:	2017-10-25
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