A DIFLUORO-SUBSTITUTED OXYALLYL INTERMEDIATE IN [4+3]CYCLOADDITION WITH CYCLOPENTADIENE AND FURAN

Authors
FOHLISCH B RADL A
Citation
B. Fohlisch et A. Radl, A DIFLUORO-SUBSTITUTED OXYALLYL INTERMEDIATE IN [4+3]CYCLOADDITION WITH CYCLOPENTADIENE AND FURAN, Journal of fluorine chemistry, 90(1), 1998, pp. 23-28
Citations number
28
Categorie Soggetti
Chemistry Inorganic & Nuclear","Chemistry Inorganic & Nuclear
Journal title
Journal of fluorine chemistry → ACNP
ISSN journal
00221139
Volume
90
Issue
1
Year of publication
1998
Pages
23 - 28
Database
ISI
SICI code
0022-1139(1998)90:1<23:ADOII[>2.0.ZU;2-U
Abstract
1-Bromo-1,3-difluoropropan-2-one (2) reacts with cyclopentadiene, fura n and 2,5-dimethylfuran in 2,2,2-trifluoroethanol/sodium 2,2,2-trifluo roethoxide to form 2,4-difluorobicyclo[ 3.2.1]oct-6-en-3-one (7b) and the 8-oxa analogues (7a, 7c). The endo orientation of the fluoro subst ituents at C-2 and C-4 indicates a concerted [4 + 3] cycloaddition of a W-configurated difluoro-oxyallyl intermediate (5) via a compact tran sition state. (C) 1998 Elsevier Science S.A. All rights reserved.