| Summary: | The isothiourea-catalyzed enantioselective 1,6-conjugate addition of <i>para</i>-nitrophenyl esters to 2,6-disubstituted <i>para</i>-quinone methides is reported. <i>para</i>-Nitrophenoxide, generated in situ from initial <i>N</i>-acylation of the isothiourea by the <i>para</i>-nitrophenyl ester, is proposed to facilitate catalyst turnover in this transformation. A range of <i>para</i>-nitrophenyl ester products can be isolated, or derivatized in situ by addition of benzylamine to give amides at up to 99% yield. Although low diastereocontrol is observed, the diastereoisomeric ester products are separable and formed with high enantiocontrol (up to 94:6 er).
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