Preparation of alkenyl cyclopropanes through a ruthenium-catalyzed tandem enyne metathesis-cyclopropanation sequence.
Acyclic enynes undergo a tandem enyne metathesis/cyclopropanation sequence in the presence of Grubbs' 1st generation metathesis catalyst and diazo compounds. In practice, the acyclic substrates in the presence of the ruthenium alkylidene first undergo a ring-closing enyne metathesis to generate cyclic 1,3-dienes; then upon addition of a diazo compound, these products are cyclopropanated selectively at the more accessible olefin. Overall, the reaction sequence converts acyclic enynes into vinyl cyclopropanes in single operation through two unique ruthenium-catalyzed transformations.
Kim
Byung Gyu
BG
Department of Chemistry, Merkert Chemistry Center, Boston College, 2609 Beacon Street, Chestnut Hill, MA 02467-3860, USA.
Snapper
Marc L
ML