Conformational Effects in Intramolecular C(sp3)-H Bond Functionalization: Gold(I)-Catalyzed Cycloisomerization of
Rubén Miguélez1, Omar Arto1, Hannah Siera2
1Department of Organic and Inorganic Chemistry, Universidad de Oviedo, Julian Clavería 8, 33006 Oviedo, Spain.
Abstract:
The use of cyclohexane derivatives displaying all possible substitution patterns has allowed us to study the influence of the conformational effects in the recently reported gold(I)-catalyzed cycloisomerization reaction of aliphatic 1-bromoalkynes that entails an unusual functionalization of a nonactivated C(sp3)-H bond. Some clear trends in terms of reactivity, regio- and stereoselectivity may be drawn from the experimental results and, in most cases, rationalized using intuitive conformational analysis arguments (i.e., equatorial/axial preferences). Occasionally, some unexpected results were also obtained, but they have also found a rational explanation. DFT calculations have been used to help us understand the underlying effects that dictate the reactivity or selectivity differences.
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