Cascade Reaction of Donor-Acceptor Cyclopropanes: Mechanistic Studies on Cycloadditions with Nitrosoarenes and cis-Diazenes.
Tandem ring opening, elimination, and cycloaddition of donor-acceptor cyclopropanes were observed in Yb(OTf)3-catalyzed cycloaddition with nitrosoarenes. The reaction results in formation of tetrahydro-1,2-oxazine instead of the normal cycloadduct isoxazolidine via in situ nitrone formation. A similar cascade sequence was observed with cis-diazines. Mechanistic studies on this unique transformation offer an entirely new approach for reaction design with donor-acceptor cyclopropanes.
Department of Chemistry, The University of Western Ontario , 1151 Richmond Street, London, ON N6A 5B7, Canada.
Tristan
T
Chidley
Department of Chemistry, The University of Western Ontario , 1151 Richmond Street, London, ON N6A 5B7, Canada.
Naresh
N
Vemula
Department of Chemistry, The University of Western Ontario , 1151 Richmond Street, London, ON N6A 5B7, Canada.
Cheryl A
CA
Carson
Department of Chemistry, The University of Western Ontario , 1151 Richmond Street, London, ON N6A 5B7, Canada.
Michael A
MA
Kerr
Department of Chemistry, The University of Western Ontario , 1151 Richmond Street, London, ON N6A 5B7, Canada.
Brian L
BL
Pagenkopf