SYNTHESIS OF PYRROLIZIN-3-ONES BY FLASH VACUUM PYROLYSIS OF PYRROL-2-YLMETHYLIDENE MELDRUMS ACID-DERIVATIVES AND 3-(PYRROL-2-YL)PROPENOIC ESTERS

Authors
CAMPBELL SE COMER MC DERBYSHIRE PA DESPINOY XLM MCNAB H MORRISON R SOMMERVILLE CC THORNLEY C
Citation
Se. Campbell et al., SYNTHESIS OF PYRROLIZIN-3-ONES BY FLASH VACUUM PYROLYSIS OF PYRROL-2-YLMETHYLIDENE MELDRUMS ACID-DERIVATIVES AND 3-(PYRROL-2-YL)PROPENOIC ESTERS, Journal of the Chemical Society. Perkin transactions. I, (15), 1997, pp. 2195-2202
Citations number
36
Categorie Soggetti
Chemistry Inorganic & Nuclear
Journal title
Journal of the Chemical Society. Perkin transactions. I → ACNP
ISSN journal
0300922X
Issue
15
Year of publication
1997
Pages
2195 - 2202
Database
ISI
SICI code
0300-922X(1997):15<2195:SOPBFV>2.0.ZU;2-E
Abstract
Monosubstituted pyrrolizin-3-ones 1 with substituents at the 1-, 5-, 6 - or 7-positions are prepared in excellent yield by flash vacuum pyrol ysis (FVP) of appropriate Meldrum's acid derivatives 2, The mechanism involves formation of the pyrrol-2-ylmethylideneketene 29, which can a lso be generated thermally from 3-(pyrrol-2-yl)propenoate esters (e.g. 30), This alternative route has been used to make a range of 2-substi tuted pyrrolizin-3-ones, again in excellent yield, The 3-oxo-3H-pyrrol izine-2-carboxylic acid 42 could not be made in this way owing to faci le decarboxylation to pyrrolizinone 1, and extension to the formation of the azaazulenone 48 was again unsuccessful.