Michael Addition onto Cyclic Enones

Jaesook Yun and co-worker from Sungkyunkwan University in Korea have recently published in Chemical Communications on a Michael addition of a boron group to cyclic enones.  They used a copper (I) chloride catalyst and taniaphos, a ferrocenyl ligand that has a phosphino and an amino groups.

Chem Comm paper

Oxaziridine Reactivities

Liping Yang and co-worker from East China Normal University have recently published in Synthesis on the N-O or C-O cleavage of oxaziridines. Depending on the conditions, an H+ source can lead to an amide and silver triflate can lead to a nitrone structure.

 

Synthesis paper

New Approach to Spiroketals

Daniel Werz and co-workers at the Institut fur Organische und Biomolekulare Chemie der Georg-August-Universitat Gottingen have recently published in JOC on the formation of spiroketals from tetrahydrofuranyl or tetrahydropyranyl cyclopropane ester substrates by undergoing a reduction-oxidation protocol, which involves the opening and closing of the three membered ring.  This new approach adds to the different ways to make spiroketal rings.

JOC paper

A Convergent Approach for Polycyclic Frameworks

Zhu-Jun Yao and co-workers at the Shanghai Institute of Organic Chemistry have recently published in JOC to show the utility of isochromenylium tetrafluoroborates, which are stable salts.

 

JOC paper

Access to Substituted Furans

Zhengkun Yu and co-worker at the Shanghai Institute of Organic Chemistry have recently published in JOC on a multi-component coupling approach to synthesize substituted furans using a palladium catalyst.

JOC paper

Vinyl Silane Containing Diene

The Diels-Alder reaction is one of the most powerful reactions in organic chemistry because it’s so darn efficient:  if you think about it you’re making two sigma bonds in one attempt.  Mark Welker and co-workers at Wayne State University have recently published in JOC on the Diels-Alder reactions that have a silyl group attached to the diene, which would lead to a Pd-catalyzed cross coupling precursor for later C-C bond forming transformations.

JOC paper

A Juvenile Hormone

Toyomi Kotaki and co-workers at the National Institute of Agrobiological Sciences and Tetsuro Shinada et al at Osaka City University have recently published in Organic Letters on the isolation and structure determination of an acyclic sesquiterpenoid that is involved in a lot of the metabolically regulatory aspects of insects.  They combined the isolation powers with synthetic approaches to determine the structure.  It was isolated from a heteropteran insect the group of insects that include the water bugs that glide on top of water and we all know that Jesus walked on water too but the J doesn’t stand for his name.

OL paper

Yet Another C-H Functionalization

Stuart Schreiber and co-worker have recently published in Organic Letters on the C-H bond functionalization of a 2-amido-benzimidazole substrate with a secondary amine.  I’m sure that he will eventually use this methodology in his combinatorial approach to look for biologically interesting molecules.

OL paper

Ketene Wittig?

Richard Taylor (University of York) and John Wood and co-worker have recently published in Organic Letters on the annelation reaction that involves the use of the Bestmann ylide, which is triphenylphosphoranylideneketene.  The ylide is an electrophile and after a nucleophile attacks the ylide, it will become a nucleophile in turn and a Michael addition will proceed to form a lactone ring.  It’s an interesting example of how creativity of combining multiple functional groups into one substrate can lead to multiple reactivities.

OL paper

[3+2] Pt-Catalyzed Cycloaddition

Nobuharu Iwasawa and co-workers have used a silyl propadienyl ether substrate as a precursor to a platinum containing 1,3-dipole reactive intermediate that will undergo a [3+2] cycloaddition to form five membered rings. This is a new entry into making five membered rings and it involves a Pt-carbene intermediate.

 

JACS paper