Reaction of N-methyl-5-tributylstannyl-4-fluoro-1H-pyrazole and its application to N-methyl-chromeno[2,3-d]pyrazol-9-one synthesis

Takeshi Hanamoto, Eri Hashimoto, Masayuki Miura, Hiroshi Furuno, Junji Inanaga

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

(Chemical Equation Presented) N-Methylation by sequential treatment of 5-tributylstannyl-4-fluoro-1H-pyrazole 1 with LDA and iodomethane regioselectively afforded the compound 2a in high yield. The addition reaction of 5-lithiated-4-fluoro-1H-pyrazole generated from 2a with a wide range of electrophiles allowed a facile introduction of different substituents at position 5 in good yields. The adduct 3d was efficiently converted to N-methyl-chromeno[2,3-d]pyrazol-9-one 9 in 3 steps.

Original languageEnglish
Pages (from-to)4736-4739
Number of pages4
JournalJournal of Organic Chemistry
Volume73
Issue number12
DOIs
Publication statusPublished - Jun 20 2008

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All Science Journal Classification (ASJC) codes

  • Organic Chemistry

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