Total Synthesis of Phenanthroquinolizidine Alkaloids Using a Building Block Strategy

Young In Jo, Cheol-Hong Cheon

Research output: Contribution to journalArticle

Abstract

A concise and general strategy for the total synthesis of the phenanthroquinolizidine alkaloids has been developed. An iterative Suzuki-Miyaura coupling reaction between the requisite aryl boronic acid, 2-bromo-4,5-dimethoxyphenyl N-methyliminodiacetate (MIDA) boronate derived from boronic acid, and a suitable bromopyridine substrate bearing a homopropargyl alcohol at the 2-position generated the desired ortho-aza-terphenyl compounds. Hydrogenation of the triple bond followed by treatment with methanesulfonyl chloride afforded their corresponding tetrahydroquinolizinium ion intermediates, which were subsequently reacted with NaBH4 to provide the desired hexahydroquinolizine products. A final oxidative electrocyclization reaction gave the target phenanthroquinolizidine natural products. This synthetic approach only requires the use of three chromatographic separations throughout the entire synthesis.

Original languageEnglish
Pages (from-to)11902-11910
Number of pages9
JournalThe Journal of organic chemistry
Volume84
Issue number18
DOIs
Publication statusPublished - 2019 Sep 20

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Boronic Acids
Alkaloids
Terphenyl Compounds
Aza Compounds
Bearings (structural)
Hydrogenation
Biological Products
Alcohols
Ions
Substrates
phenanthroquinolizidine
methanesulfonyl chloride

ASJC Scopus subject areas

  • Organic Chemistry

Cite this

Total Synthesis of Phenanthroquinolizidine Alkaloids Using a Building Block Strategy. / Jo, Young In; Cheon, Cheol-Hong.

In: The Journal of organic chemistry, Vol. 84, No. 18, 20.09.2019, p. 11902-11910.

Research output: Contribution to journalArticle

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