ortho-Quinone methides from para-quinones: total synthesis of rubioncolin B.
نویسندگان
چکیده
A concise synthesis of rubioncolin B is described, which features an unprecedented intramolecular Diels-Alder reaction involving an ortho-quinone methide and a naphthofuran moiety. The ortho-quinone methide is generated through a surprisingly facile tautomerization of a para-quinone.
منابع مشابه
Three-component coupling using arynes and DMF: straightforward access to coumarins via ortho-quinone methides.
ortho-Quinone methides, arising from a formal [2+2] cycloaddition between arynes and DMF, were found to facilely undergo a [4+2] cycloaddition with ester enolates or ketenimine anions to produce diverse coumarins in a straightforward manner.
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We disclose herein a highly enantioselective protocol for the Brønsted acid-catalyzed addition of indoles and phenols to in situ-generated ortho-quinone methides which deliver broadly substituted diarylindolylmethanes and triarylmethanes, respectively, in a one-pot reaction under very mild conditions. A chiral phosphoric acid catalyst has been developed for this process serving to convert the s...
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ورودعنوان ژورنال:
- Journal of the American Chemical Society
دوره 130 29 شماره
صفحات -
تاریخ انتشار 2008