TfOH-catalyzed tandem cyclopropane ring enlargement/C-C formation/etherification of alkynylcyclopropanes and 1,3-diketones to cyclobutane-fused dihydrofurans.
نویسندگان
چکیده
A new type of TfOH-catalyzed tandem cyclopropane ring enlargement/C-C formation/etherification reaction between alkynylcyclopropanes and 1,3-diketones to cyclobutane-fused dihydrofurans is described. The reaction tolerates a range of aryl and alkyl substituents with moderate to good yields.
منابع مشابه
Gold(I)-catalyzed ring expansions of unactivated alkynylcyclopropanes to (e)-2-alkylidenecyclobutanamines in the presence of sulfonamides.
The ring expansion of cyclopropane derivatives provides a powerful method to construct synthetically useful four-membered carbocycles. Herein, a new type of gold(I)-catalyzed ring expansion of an unactivated alkynylcyclopropane/sulfonamide trapping strategy to (E)-2-alkylidenecyclobutanamines was described. The reaction tolerates a range of aryl and alkyl substituents with moderate to good yields.
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ورودعنوان ژورنال:
- Chemical communications
دوره 47 2 شماره
صفحات -
تاریخ انتشار 2011