1229617-77-9Relevant academic research and scientific papers
Study of the chemoselectivity of Grignard reagent addition to substrates containing both nitrile and Weinreb amide functionalities
Harikrishna, Kommidi,Rakshit, Ananya,Aidhen, Indrapal Singh
, p. 4918 - 4932 (2013/08/23)
Several substrates containing both cyano and Weinreb amide functionalities have been synthesized to study the chemoselectivity of their reactions with organomagnesium bromides (ArMgBr and RMgBr). Excellent chemoselectivity towards the Weinreb amide was observed in most cases, even in the presence of excess Grignard reagent, affording cyano ketones in good-to-excellent yields. The reactions of various substrates containing both nitrile and Weinreb amide functionalities with Grignard reagents have been studied. The Weinreb amide reacts chemoselectively with excess Grignard reagent to give the corresponding cyano ketones in good yields. This chemoselectivity has been exploited for the synthesis of a key coumarin intermediate towards the 5-lipoxygenase inhibitor MK-0633. Copyright
A practical synthesis of 5-lipoxygenase inhibitor MK-0633
Gosselin, Francis,Britton, Robert A.,Davies, Ian W.,Dolman, Sarah J.,Gauvreau, Danny,Hoerrner, R. Scott,Hughes, Gregory,Janey, Jacob,Lau, Stephen,Molinaro, Carmela,Nadeau, Christian,Oshea, Paul D.,Palucki, Michael,Sidler, Rick
supporting information; experimental part, p. 4154 - 4160 (2010/09/09)
Practical, chromatography-free syntheses of 5-lipoxygenase inhibitor MK-0633 p-toluenesulfonate (1) are described. The first route used an asymmetric zincate addition to ethyl 2,2,2-trifluoropyruvate followed by 1,3,4-oxadiazole formation and reductive amination as key steps. An improved second route features an inexpensive diastereomeric salt resolution of vinyl hydroxy-acid 22 followed by a robust end-game featuring a through-process hydrazide acylation/1,3,4-oxadiazole ring closure/salt formation sequence to afford MK-0633 p-toluenesulfonate (1).
