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Long-range diastereoselectivity in Ugi reactions of 2-substituted dihydrobenzoxazepines.

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.

SUBMITTER: Banfi L

PROVIDER: S-EPMC3170203 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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Long-range diastereoselectivity in Ugi reactions of 2-substituted dihydrobenzoxazepines.

Banfi Luca L Basso Andrea A Cerulli Valentina V Rocca Valeria V Riva Renata R

Beilstein journal of organic chemistry 20110713

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 tetrahy ...[more]

PMID: 21915196

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