New Way to Make Amide Bonds

Jeffrey Johnston and co-workers at Vanderbilt University have published in Nature on a new way to make amide bonds by reacting a bromo-nitro compound and an amine group in the presence of NIS.

Nature paper

Intramolecular C-H Activation with Palladium

Jing-Hua Li and co-workers at Zhejiang University of Technology have published in Synthesis on a palladium/copper coupled intramolecular C-H activation to synthesize an indole ring.  The way they made the C-H activation precursor (enamine) was by grinding cyclohexan-1,3-dione and aniline together – something you don’t usually see in a typical procedure…

Synthesis

Asymmetric Oxidative Coupling with Cu(OTf)2

Liu-Zhu Gong and co-workers at the University of Science and Technology in China have published in ACIEE on a copper triflate catalyzed C-H activation reaction that uses DDQ as the stoichiometric oxidant.  The reaction couples a benzyl position and a malonate group to enantioselectively build a new carbon center.

ACIEE paper

Claisen Rearrangement to Access Chiral Quaternary Carbons

Derrick Clive and co-worker at the University of Alberta have published in JOC on Claisen rearrangement approach to access a chiral quaternary carbon center.  The stereoselectivity comes from substrate control where the chiral center originates from serine.  The dihydropyran Claisen rearrangement precursor is synthesized from an intramolecular Michael addition of an amine to an alkynone.  The presumed vinyl ether is not isolated as they react an alcohol with butyl vinyl ether in the presence of Hg(OAc)2 to spontaneously undergo the Claisen rearrangement.

JOC paper

Anthopogochromane

Anthopogochromane A, a tetracyclic compound isolated from the Chinese medicinal plant Rhododendron anthopogonoides, was found to have anti-inflammatory activities.  The tetracyclic compound, anthopogochromane A,  had an IC50 of 114 micromolar while the bicyclic compound, anthopogochromane B, had an IC50 value of 63 micromolar.  The anti-inflammatory activity was calculated by measuring the histamine released upon addition of histamine releasers (compound 48/80).

JNP paper

Indanone Synthesis by Kicking out Thiophene

Nicolai Cramer and co-workers at ETH Zurich have published in Synlett on a rhodium catalyzed indanone synthesis that involves breaking open a cyclobutanol and kicking off a thiophene group to give rise to a highly enantioselective reaction.

Synlett paper

Carbonyl Ylide Approach to Seven Membered Rings

Martin Maier and co-workers at the Universitat Tubingen have published in Organic Letters on a carbonyl ylide cycloaddition with allyl propiolate to synthesize a guaianolide 5,7-bicyclic ring system.

OL paper

Cope Rearrangement to Seven Membered Rings

Seven membered rings are hard to make but Vladimir Birman and co-workers at Washington University have published in Organic Letters on a [3,3] Cope rearrangement approach to access seven membered rings.

OL paper

Ruthenium Catalyzed Isotopic Labeling

Hironao Sajiki and co-workers at Gifu Pharmaceutical University have published in Chem Comm on a ruthenium on carbon method to exchange protons with deuterium on a sugar in the presence of hydrogen gas and D2O.  You probably can’t have any alkenes in your molecule since they might get hydrogenated.

Chem Comm paper

Iridacycles

Yasushi Tsuji and co-workers at Kyoto University have published in JACS on the synthesis of 2-quinolones from alkynes and N-arylcarbamoyl chlorides using an iridium catalyst.

JACS paper