Preparation of 2-Fluoro-3-aminophenylboronates
via Directed ortho-Metalation

Paul E. Zhichkin; Sergiy G. Krasutsky; Catherine M. Beer; W. Martin Rennells; Seung H. Lee; Jin-Ming Xiong

doi:10.1055/s-0030-1260019

PAPER

Preparation of 2-Fluoro-3-aminophenylboronates via Directed ortho-Metalation

Paul E. Zhichkin^a, Sergiy G. Krasutsky*^a, Catherine M. Beer^a, W. Martin Rennells^a, Seung H. Lee^b, Jin-Ming Xiong^b
^a Medicinal Chemistry Department, AMRI, 26 Corporate Circle, P.O. Box 15098, Albany, NY, 12212, USA
Fax: +1(518)5122079; e-Mail: sergiy.krasutsky@amriglobal.com;
^b Gilead Sciences, Inc., 36 East Industrial Rd., Branford, CT 06405, USA

Abstract

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Abstract

The aromatic amine in fluoroanilines was protected with 2,2,5,5-tetramethyl-1-aza-2,5-disila-cyclopentane (stabase) in order to direct metalation ortho to the fluorine. A series of novel 2-fluoro-3-aminophenylboronates were prepared after quenching the metalated intermediate with triisopropylborate and deprotection in situ. The presented method is convenient and scalable, because all of the synthetic steps use crude intermediates. Several transformations are carried out in the same pot, and the final boronates are easily purified crystalline materials.

Key words

boronates - metalation - regioselectivity - protecting groups - amines

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Referenzen

References

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