Stereocontrolled synthesis of the aconitine D ring from D-glucose.

The synthesis of a fully oxygenated aconitine D ring precursor from (D)-(+)-glucose is described. The route features a highly diastereoselective alkynyl Grignard ketone addition and a base-mediated enelactone to 1,3-diketone rearrangement.

Direct formation of 4,5-disubstituted carbazoles via regioselective dilithiation.

Carbazoles are widely exploited for their interesting photophysical and electronic properties, however bay (4,5-) functionalization is challenging, and previously inaccessible through carbazole C-H activation. We report a simple methodology which introduces a range of versatile 4,5-functionality, enabling the wider investigation of ring annulation and close proximity effects on carbazole properties.

Tandem Aryne-Capture/Sigmatropic Rearrangement as a Metal-Free Entry to Functionalized N-Aryl Pyrrolidines.

We report a new method for the synthesis of novel N-aryl proline analogues. By reacting an aryne precursor with N-(2-malonyl) tetrahydropyridines in the presence of tetrabutylammonium fluoride (TBAF), a tandem aryne-capture/anion isomerisation/[2,3]-sigmatropic rearrangement is induced, leading to good yields of 3-substituted N-aryl-2-acylpyrrolidines. These products are known subunits of biological probes, sensors and drug-like fragments, and are not easily accessed directly by other methods. The reaction is also notable as the first [2,3]-rearrangement of cyclic ammonium ylides at room temperature.