Diastereoselective 1,3-dipolar cycloaddition of nitrones to donor-acceptor cyclopropanes catalyzed by a calcium(II)
Caroline M Braun1, Elizabeth A Congdon, Kristine A Nolin
1University of Richmond , 28 Westhampton Way, Richmond, Virginia 23173, United States.
Abstract:
Calcium triflate has been identified as an efficient catalyst for the cycloaddition of nitrones to donor-acceptor cyclopropanes. The reaction proceeds with good to excellent yields of the corresponding tetrahydro-1,2-oxazines with high levels of diastereoselectivity. The generality of the reaction allowed for the synthesis of tetrahydro-1,2-oxazines bearing alkyl, aryl, and heteroaromatic substitution.
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