Rhodium-, copper- and iridium-catalyzed reactions of the (13)C-labelled diazo carbonyl substrates 18* and 19* were performed. Results obtained from copper- and iridium-catalyzed reactions of the (13)C-labelled α-diazo β-keto ester 19* indicate that either or both of these reactions do not proceed via a free oxonium ylide but instead follow a competing non-ylide route that delivers apparent [2,3...

In the title salt, C9H8NO(+)·C4H5O4 (-), the isoquinolinium ring system is approximately planar [r.m.s deviation = 0.011 (2) Å]. In the crystal, adjacent cations and anions are linked by O-H⋯O and N-H⋯O hydrogen bonds, forming columns along the b axis. The columns are connected by weak C-H⋯O inter-actions into a three-dimensional network.

Photochemical excitation of a diaryldiazomethane with an ortho-acetal both in solution and in crystals led to products that originate from the expected diarylcarbene and form an intramolecular oxonium ylide. While crystals strongly favored the formation of a benzocyclobutane by intramolecular hydrogen abstraction in the triplet carbene, reactions in benzene led exclusively to products that deri...

the use of a recyclable phase transfer catalyst, sio2-peg-imbr, is demonstrated in a simple and highly efficient synthesis of phenacyl derivatives by nucleophilic substitution reaction of phenacyl halides with different anions in water. advantages of this system are easy work-up, moderate to good yields, and recyclable catalyst. the catalyst can be recycled and reused several times with no loss...

This paper describes the determination of fatty acid composition of coffee, citrus and rum distillery wastes using reversed-phase high-performance liquid chromatography (RP-HPLC). Lipid extracts of the waste samples are derivatized with phenacyl bromide and their phenacyl esters are separated on a C8 reversed-phase column by using continuous gradient elution with water and acetonitrile. The pre...

The use of ylides of P, N, As or S as ligands toward transition metals is still a very active research area in organometallic chemistry. This fact is mainly due to the nucleophilic character of the ylides and to their particular bonding properties and coordination modes. They can behave as monodentate or bidentate –chelate or bridging– species, they can be used as chiral auxiliary reagents, the...