Premium
Oxidative Cyclization Reaction of 2‐Aryl‐Substituted Cinnamates To Form Phenanthrene Carboxylates by Using MoCl 5
Author(s) -
Wehming Kathrin,
Schubert Moritz,
Schnakenburg Gregor,
Waldvogel Siegfried R.
Publication year - 2014
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.201403442
Subject(s) - cinnamates , chemistry , aryl , phenanthrene , substituent , reagent , oxidative coupling of methane , naphthalene , organic chemistry , coupling reaction , medicinal chemistry , combinatorial chemistry , catalysis , alkyl
The oxidative cyclization reaction of 2‐aryl cinnamates and derivatives thereof can be easily performed with MoCl 5 as the oxidant. This powerful reagent allows oxidative coupling reactions for which other reagents fail. The best results are obtained when the 2‐phenyl substituent of the cinnamate is equipped with two methoxy groups. Even iodo moieties in the bay region of phenanthrene are tolerated under the reaction conditions. If naphthalene moieties are involved, a rearrangement of the skeleton occurs, providing an elegant route to highly functionalized angular arenes. The cyclization is demonstrated for 15 example substrates with isolated yields of up to 99 % for the phenanthrene derivative. The broad scope of the reaction underlines the usefulness of MoCl 5 and MoCl 5 /TiCl 4 in the oxidative coupling reaction.