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Synlett 2002(9): 1556-1557
DOI: 10.1055/s-2002-33540
SPOTLIGHT
© Georg Thieme Verlag Stuttgart · New York

The N-Cumyl Group for Facile Manipulation of Carboxamides, Sulfonamides and Aryl O-Carbamates
Post-Directed ortho Metalation

Costa Metallinos*
Boston College Chemistry Department, Merkert Center, 2609 Beacon St., Chestnut Hill, MA 02467, USA
e-Mail: metallin@bc.edu;
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Publication History

Publication Date:
17 September 2002 (online)

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Directed metalation groups (DMGs) are sometimes compromised by the inability to convert them to different functionalities under mild conditions in post-directed ortho metalation (DoM) steps. [1] The advent of N-cumyl modified carboxamide, sulfonamide and O-carbamate DMGs, [2] whose primary advantages over analogous N-t-Bu [3] and other N-alkyl systems rest in fast and/or mild hydrolysis post-DoM, has opened new possibilities for the manipulation of substituted aromatics (Scheme 1). Starting materials are easily prepared by treating the appropriate benzoyl or sulfonyl chlorides with cumyl amine [4] for access to benzamides and sulfonamides, respectively, or by treating phenyl chloroformate with a secondary N-alkyl-N-cumyl amine [5] for O-carbamates.

This Spotlight reviews several applications of N-cumyl-substituted functional groups in organic synthesis since the preliminary results of 1999. [2]

Scheme 1

    References

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    Thieme Connect
  • 4b

    Cumyl amine is also commercially available from TCI America: catalogue no. C1293.
    Thieme Connect
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7

Ang, P. J. A.; Metallinos, C.; Snieckus, V., unpublished results.

14

Metallinos, C.; Szillat, H.; Taylor, N. J.; Snieckus, V., manuscript in preparation.