Issue 6 is the 150th issue of OBC. Since the first issue was published in January 2003, the journal has achieved tremendous success. With an Impact Factor^® of 3.167, can any other 'young' journal boast such highly cited papers, published quickly after independent peer review? The OBC editorial team would like to thank all our authors and referees for their support over the last six years and we hope you enjoy our 150th issue. 

The issue's front cover promotes the Hot Article by Kenso Soai and colleagues at Tokyo University of Science, Japan. In their article, the team combine a clay with a metal complex to make an effective catalyst for a selective organic reaction. 

Lithium salts are important drugs for patients suffering from bipolar disorder and scientists believe that they could also be used to treat amyotrophic lateral sclerosis and Alzheimer's disease. Kay Severin and colleagues at the Federal Polytechnic School of Lausanne, Switzerland, describe the synthesis of a metallacrown complex that can be used to sense low millimolar concentrations of lithium ions in water or human serum. They illustrate their work on the inside front cover.

Organic synthesis is well covered in this issue's review articles. In his Emerging Area, Tom Sheppard at University College London, UK, reviews metal-catalysed methods for interconverting aryl halides and directly halogenating aromatic systems. And Mark Rizzacasa and Annett Pollex, at the University of Melbourne, Australia, outline the scope and limitations of the hetero-Diels-Alder reaction for making spiroketal systems in their Perspective.