Structural analysis and reactivity of unusual tetrahedral intermediates enabled by SmI2-mediated reduction of barbituric acids: vinylogous N-acyliminium additions to a-hydroxy-N-acyl-carbamides†
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چکیده
Structural characterisation and reactivity of new tetrahedral intermediates based on a highly modular barbituric acid scaffold, formed via chemoselective electron transfer using the SmI2–H2O reagent, are reported. Lewis acid promoted cleavage of bicyclic a-amino alcohols affords vinylogous N-acyliminium ions, which undergo selective (>95 :5, 1,4 over 1,2) capture with a suite of diverse nucleophiles in a practical sequence to biologically active uracil derivatives.
منابع مشابه
Structural analysis and reactivity of unusual tetrahedral intermediates enabled by SmI2-mediated reduction of barbituric acids: vinylogous N-acyliminium additions to α-hydroxy-N-acyl-carbamides.
Structural characterisation and reactivity of new tetrahedral intermediates based on a highly modular barbituric acid scaffold, formed via chemoselective electron transfer using the SmI2-H2O reagent, are reported. Lewis acid promoted cleavage of bicyclic α-amino alcohols affords vinylogous N-acyliminium ions, which undergo selective (>95 : 5, 1,4 over 1,2) capture with a suite of diverse nucleo...
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