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Published on: February 7, 2019
Long-range diastereoselectivity in Ugi reactions of 2-substituted dihydrobenzoxazepines
Luca Banfi1, Andrea Basso, Valentina Cerulli
1Department of Chemistry and Industrial Chemistry, University of Genova, I-16146 Genova, Italy.
Abstract:
The Ugi reaction of 2-substituted dihydrobenzoxazepines was found to proceed with unexpectedly good diastereoselectivitiy (diastereoisomeric ratios up to 9:1), despite the large distance between the pre-existing stereogenic centre and the newly generated one. This result represents the first good 1,4 asymmetric induction in an Ugi reaction as well as the first example of diastereoselective Ugi reaction of seven membered cyclic imines. It allows the diversity-oriented synthesis of various tetrahydro[f][1,4]benzoxazepines.
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