Direct synthesis of pyrazolo[5,1-a]isoindoles via intramolecular palladium-catalyzed C-H bond activation

Young Lok Choi, Hyuk Lee, Bum Tae Kim, Kihang Choi, Jung Nyoung Heo

Research output: Contribution to journalArticle

27 Citations (Scopus)

Abstract

An efficient, direct synthesis of pyrazolo-[5,1-a]isoindoles employing a palladium-catalyzed intramolecular C-H bond activation of 1-(2-halobenzyl) pyrazoles has been developed. The use of lithium chloride (LiCl) was found to be essential in these reactions, to suppress further C-H bond activation at the C-3 position of pyrazolo[5,1-a]isoindole, when C-3 is unsubstituted. This protocol can be applied to the synthesis of a pyrazolo[5,1-a]isoquinoline possessing a six-membered central ring system and a fully substituted pyrazolo[5,1-a]isoindole using sequential intra- and intermolecular C-H bond activation.

Original languageEnglish
Pages (from-to)2041-2049
Number of pages9
JournalAdvanced Synthesis and Catalysis
Volume352
Issue number11-12
DOIs
Publication statusPublished - 2010 Sep 13

Fingerprint

Palladium
Chemical activation
Pyrazoles
Lithium Chloride
Lithium
pyrazolo(5,1-a)isoindole

Keywords

  • C-H activation
  • Direct arylation
  • Palladium
  • Pyrazoles

ASJC Scopus subject areas

  • Catalysis
  • Organic Chemistry

Cite this

Direct synthesis of pyrazolo[5,1-a]isoindoles via intramolecular palladium-catalyzed C-H bond activation. / Choi, Young Lok; Lee, Hyuk; Kim, Bum Tae; Choi, Kihang; Heo, Jung Nyoung.

In: Advanced Synthesis and Catalysis, Vol. 352, No. 11-12, 13.09.2010, p. 2041-2049.

Research output: Contribution to journalArticle

Choi, Young Lok ; Lee, Hyuk ; Kim, Bum Tae ; Choi, Kihang ; Heo, Jung Nyoung. / Direct synthesis of pyrazolo[5,1-a]isoindoles via intramolecular palladium-catalyzed C-H bond activation. In: Advanced Synthesis and Catalysis. 2010 ; Vol. 352, No. 11-12. pp. 2041-2049.
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