Premium
Temperature‐Controlled Stereodivergent Synthesis of 2,2′‐Biflavanones Promoted by Samarium Diiodide
Author(s) -
Soto Martín,
Soengas Raquel G.,
Silva Artur M. S.,
GotorFernández Vicente,
RodríguezSolla Humberto
Publication year - 2019
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201902927
Subject(s) - selectivity , samarium diiodide , samarium , stereoselectivity , chemistry , stereochemistry , ring (chemistry) , catalysis , organic chemistry
In this work, the first example of a radical stereodivergent reaction directed towards the stereoselective synthesis of both ( R*,R* )‐ and ( R*,S* )‐2,2′‐biflavanones promoted by samarium diiodide is reported. Control experiments showed that the selectivity of this reaction was exclusively controlled by the temperature. It was possible to generate a variety of 2,2′‐biflavanones bearing different substitution patterns at the aromatic ring in good‐to‐quantitative yields, being both stereoisomers of the desired compounds obtained with total or high control of selectivity. A mechanism that explains both the generation of the corresponding 2,2′‐biflavanones and the selectivity is also discussed. The structure and stereochemistry determination of each isomer was unequivocally elucidated by single‐crystal X‐ray diffraction experiments.