Abstract:
: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.
journal_name
Chem Pharm Bull (Tokyo)journal_title
Chemical & pharmaceutical bulletinauthors
Okado R,Nowaki A,Matsuo J,Ishibashi Hdoi
10.1248/cpb.60.21subject
Has Abstractpub_date
2012-01-01 00:00:00pages
21-2issue
1eissn
0009-2363issn
1347-5223pii
JST.JSTAGE/cpb/60.21journal_volume
60pub_type
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