NEW INTERMOLECULAR AND INTRAMOLECULAR CARBOCYCLIZATIONS AND HETEROCYCLIZATIONS OF 4-METHYL-4-TRICHLOROMETHYLCYCLOHEXA-2,5-DIEN-1-ONE AND ITS ETA(4)-RHODIUMCYCLOPENTADIENYL COMPLEX UNDER THE ACTION OF N-BUTHYLLITHIUM - FORMATION OF FUNCTIONALLY-SUBSTITUTED TRICYCLIC SPIROFURAN AND BICYCLO[2.2.1]HEPTADIENE SYSTEMS

Authors
SERGEEV SV NIKANOROV VA ZVEREV DV PETROVSKII PV
Citation
Sv. Sergeev et al., NEW INTERMOLECULAR AND INTRAMOLECULAR CARBOCYCLIZATIONS AND HETEROCYCLIZATIONS OF 4-METHYL-4-TRICHLOROMETHYLCYCLOHEXA-2,5-DIEN-1-ONE AND ITS ETA(4)-RHODIUMCYCLOPENTADIENYL COMPLEX UNDER THE ACTION OF N-BUTHYLLITHIUM - FORMATION OF FUNCTIONALLY-SUBSTITUTED TRICYCLIC SPIROFURAN AND BICYCLO[2.2.1]HEPTADIENE SYSTEMS, Russian chemical bulletin, 46(8), 1997, pp. 1454-1457
Citations number
10
Categorie Soggetti
Chemistry
Journal title
Russian chemical bulletin → ACNP
ISSN journal
10665285
Volume
46
Issue
8
Year of publication
1997
Pages
1454 - 1457
Database
ISI
SICI code
1066-5285(1997)46:8<1454:NIAICA>2.0.ZU;2-Y
Abstract
Treatment with (BuLi)-Li-n in THF (-60-0 degrees C) causes 4-methyl-4- trichloromethylcyclohexa-2,5-dien-1-one and its exo-eta(4)-coordinated (by a RhCp-group) pi-diene metal complex to undergo reactions of two new types: intermolecular autocondensation-heterocyclization (affordin g piro-[benzofuran-2,1'-cyclohexa-2',5'-dien]-6-one; 24%) and intramol ecular carbocyclization (yielding ]hepta-2,5-diene)(eta(5)-cyclopentad ienyl)rhodium; 77%). Both processes are assumed to involve the formati on of an unusual gem-CCl2Li substituted para-semiquinoid intermediate, the conformation of the six-membered diene ring of which (planar or a boat-like) governs its subsequent intra- or intermolecular stereospec ific carbonyl condensations.