Premium
Inter‐ and intramolecular hetero diels‐alder reactions, XXI. Intramolecular hetero diels‐alder reaction of alkylidene‐1,3‐dicarbonyl compounds. Experimental evidence for an asymmetric transition state
Author(s) -
Tietze Lutz F.,
Brumby Thomas,
Brand Siegbert,
Bratz Matthias
Publication year - 1988
Publication title -
chemische berichte
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.667
H-Index - 136
eISSN - 1099-0682
pISSN - 0009-2940
DOI - 10.1002/cber.19881210318
Subject(s) - chemistry , intramolecular force , knoevenagel condensation , diels–alder reaction , adduct , aldehyde , intramolecular reaction , medicinal chemistry , stereochemistry , polymer chemistry , organic chemistry , catalysis
The intramolecular hetero Diels‐Alder reaction of heterodienes 13 is described. The heterodienes, which are obtained in situ by Knoevenagel condensation of aldehydes 12a – e with dimethylbarbituric acid ( 2 ), yield the cycloadducts 14a – e/15a – e and the ene adducts 16a, c – e/17a, c – e . The ratio of 14 / 15 was determined by HPLC. The resulting data are interpreted as experimental evidence of an asymmetrical transition state of the Diels‐Alder reaction.