An Efficient Approach to 3-Bromo-6-chloro-phenanthrene-9,10-dione
ABSTRACT A practical and efficient synthesis of 3-bromo-6-chloro-phenanthrene-9,10-dione was developed and demonstrated on a large scale. The synthetic approach involves six chemical steps and two isolations in 73% overall yield. The key transformations feature an anionic cyclization for generation of the phenanthrene ring, followed by sequential tribromination and hydrolysis for the incorporation of the bromo-diketone functionality.
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ABSTRACT: A practical, kilogram-scale chromatography-free synthesis of mPGE synthase I inhibitor MK-7285 is described. The route features a convergent assembly of the core phenanthrene unit via amide-directed ortho-metalation and proximity-induced anionic cyclization, followed by imidazole synthesis and late-stage cyanation.The Journal of Organic Chemistry 09/2009; 74(20):7790-7. · 4.64 Impact Factor