TY  - JOUR
AU  - Weber, Anja
AU  - Breugst, Martin
AU  - Pietruszka, Jörg
TI  - Experimental and Computational Investigations of the Reactions between α,β‐Unsaturated Lactones and 1,3‐Dienes by Cooperative Lewis Acid/Brønsted Acid Catalysis
JO  - Angewandte Chemie / International edition
VL  - 59
IS  - 42
SN  - 1521-3773
CY  - Weinheim
PB  - Wiley-VCH
M1  - FZJ-2020-03839
SP  - 18709 - 18716
PY  - 2020
AB  - The reactions of α,β‐unsaturated δ‐lactones with activated dienes such as 1,3‐dimethoxy‐1‐[(trimethylsilyl)oxy]‐1,3‐butadiene (Brassard's diene) are barely known in literature and show high potential for the synthesis of isocoumarin moieties. An in‐depth investigation of this reaction proved a stepwise mechanism via the vinylogous Michael‐products. Subsequent cyclisation and oxidation by LHMDS and DDQ, respectively, provided six mellein derivatives (30–84 %) and four angelicoin derivatives (40–78 %) over three steps. DFT‐calculations provide insights into the reaction mechanism and support the theory of a stepwise reaction.
LB  - PUB:(DE-HGF)16
C6  - pmid:32567075
UR  - <Go to ISI:>//WOS:000559994400001
DO  - DOI:10.1002/anie.202008365
UR  - https://juser.fz-juelich.de/record/885456
ER  -