Further Studies of Benzothiazine Metalation

Dedicated to Professor Scott E. Denmark on the occasion of his 60^th birthday

Abstract

Treatment of benzothiazines 3 and 8 with butyllithium resulted in deprotonation at C3 to afford the corresponding organolithium species. These compounds could be trapped with a variety of electrophiles to give products in high yield. Some limitations to the processes chiefly based on steric effects were uncovered. Interesting and potentially useful side reactions were also established.

Key words

heterocycles - benzothiazine - metalation - alkylation - sulfoximine

• References

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