Streocontrolled Construction of Six Vicinal Stereogenic Centers on Spiropyrazolones via Organocascade Michael/Michael/1,2-Addition Reactions
نویسندگان
چکیده
منابع مشابه
Enantioselective concomitant creation of vicinal quaternary stereogenic centers via cyclization of alkynols triggered addition of azlactones
An asymmetric cyclization of alkynols triggered addition of azlactones catalyzed by a combined catalyst system consisting of a chiral gold phosphate and a phosphoric acid produces conformationally restricted amino acid precursors bearing vicinal quaternary stereogenic centers in high levels of stereoselectivity. 2011 Elsevier Ltd. All rights reserved. The enantioselective construction of quater...
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[reaction: see text] Photochemical irradiation of crystalline (2R,4S)-2-carbomethoxy-4-cyano-2,4-diphenyl-3-butanone 1 led to highly efficient decarbonylation reactions. Experiments with optically pure and racemic crystals showed that the intermediate radical pairs undergo a highly diastereo- and enantiospecific radical-radical combination that leads to the formation of two adjacent stereogenic...
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ژورنال
عنوان ژورنال: Organic Letters
سال: 2014
ISSN: 1523-7060,1523-7052
DOI: 10.1021/ol501093v