Formal [4+2] cycloaddition of di-tert-butyl 2-ethoxycyclobutane-1,1-dicarboxylate with ketones or aldehydes and tandem lactonization.

نویسندگان

  • Ryohei Okado
  • Aya Nowaki
  • Jun-Ichi Matsuo
  • Hiroyuki Ishibashi
چکیده

A catalytic amount of tin(IV) chloride catalyzed formal [4+2] cycloaddition reaction of di-tert-butyl 2-ethoxycyclobutane-1,1-carboxylate with ketones or aldehydes to give diethyl 6-ethoxydihydro-2H-pyran-3,3(4H)-dicarboxylates, whereas two equivalents of trimethylsilyl triflate promoted tandem [4+2] cycloaddition and lactonization to afford 3-oxo-2,6-dioxabicyclo[2.2.2]octane-4-carboxylate esters.

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عنوان ژورنال:
  • Chemical & pharmaceutical bulletin

دوره 60 1  شماره 

صفحات  -

تاریخ انتشار 2012