Zinc-Catalyzed Stereo- and Regioselective 1,4-Hydrative Fluorination of 3-En-1-ynamides with Selectfluor
摘要:
AbstractZinc‐catalyzed 1,4‐oxofluorinations of 3‐en‐1‐ynamides with Selectfluor in acetonitrile/water proceeded with high regio‐ and stereoselectivity, giving E‐configured γ‐fluoro‐α,β‐unsaturated amides efficiently. Our control experiments indicate that kinetically unstable C‐bound zinc dienolates are chemically reactive to undergo SE2′‐electrophilic fluorinations whereas the detectable O‐bound dienolates preferably undergo protodemetalation reactions instead.magnified image
Total Synthesis and Structural Confirmation of Brevisamide, a New Marine Cyclic Ether Alkaloid from the Dinoflagellate <i>Karenia brevis</i>
作者:Takefumi Kuranaga、Tomohiro Shirai、Daniel G. Baden、Jeffrey L. C. Wright、Masayuki Satake、Kazuo Tachibana
DOI:10.1021/ol802426v
日期:2009.1.1
The first total synthesis of brevisamide (1) has been accomplished in 21 linear steps starting from cis-but-2-ene-1,4-diol. A synthetic highlight is the Suzuki−Miyaura coupling between an ether ring fragment and a dienol side chain. This result confirmed the structure of 1 isolated from the dinoflagellate Karenia brevis.