Aminoxylation directed domino reactions

ORGN 631

Min Lu, szlucifer@pmail.ntu.edu.sg, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore, Singapore
Highly functionalized tetrahydro-1,2-oxazines with up to 3 stereogenic centers have been synthesized in excellent enantio- (≥99% e.e.) and complete diastereo-selectivities (>99:1 d.r.) in up to 90% yields, following a novel organocatalytic domino α-aminoxylation/aza-Michael reaction of acyclic nitroalkenals for asymmetric installation of both C-O and C-N bonds. Furthermore, DFT calculations reveal an unprecedented transition state in that a molecule of water assists the C-N bond forming step through dual H bonds.