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A simple base-mediated halogenation of acidic sp2 C-H bonds under noncryogenic conditions.

ABSTRACT: A new method has been developed for in situ halogenation of acidic sp(2) carbon-hydrogen bonds in heterocycles and electron-deficient arenes. Either selective monohalogenation or one-step exhaustive polyhalogenation is possible for substrates possessing several C-H bonds that are flanked by electron-withdrawing groups. For the most acidic arenes, such as pentafluorobenzene, K(3)PO(4) base can be employed instead of BuLi for metalation/halogenation sequences.

SUBMITTER: Do HQ

PROVIDER: S-EPMC2635093 | biostudies-literature | 2009 Jan

REPOSITORIES: biostudies-literature

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A simple base-mediated halogenation of acidic sp2 C-H bonds under noncryogenic conditions.

Do Hien-Quang HQ Daugulis Olafs O

Organic letters 20090101 2

A new method has been developed for in situ halogenation of acidic sp(2) carbon-hydrogen bonds in heterocycles and electron-deficient arenes. Either selective monohalogenation or one-step exhaustive polyhalogenation is possible for substrates possessing several C-H bonds that are flanked by electron-withdrawing groups. For the most acidic arenes, such as pentafluorobenzene, K(3)PO(4) base can be employed instead of BuLi for metalation/halogenation sequences. ...[more]

PMID: 19102661

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