Base-catalyzed Diels-Alder reactions of 2H-pyran-2,5-diones: a mild approach to basiliolide B.
نویسندگان
چکیده
A new class of base-catalyzed Diels-Alder reactions of 2H-pyran-2,5-diones has been developed using catalytic amount of dicyclohexylmethylamine in tert-butyl alcohol. This method has been successfully employed for construction of the tricyclic core of basiliolide B at room temperature with good yields and exclusive endo selectivity.
منابع مشابه
Base-promoted annulation of α-hydroxy ketones and dimethyl but-2-ynedioate: straightforward access to pyrano[4,3-a]quinolizine-1,4,6(2H)-triones and 2H-pyran-2,5(6H)-diones.
A novel and efficient cascade annulation of tertiary α-hydroxy ketones and dimethyl but-2-ynedioate is reported. The reaction, which only requires a base as the promoter, provides a straightforward access to polysubstituted pyrano[4,3-a]quinolizine-1,4,6(2H)-triones and 2H-pyran-2,5(6H)-diones under very mild reaction conditions.
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ورودعنوان ژورنال:
- Organic letters
دوره 10 24 شماره
صفحات -
تاریخ انتشار 2008