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The article presents information on a study which finds a new and highly chemoselective procedure for the halogen. The study finds that the development of a protecting-group-free halogen-metal exchange reaction with high functional group and acidic proton compatibility remains a large challenge in organornetallic and organic chemistry. The study is promoted by the Astellas Foundation, the Sumitomo Foundation in the United States. According to the researchers, in the case of bromobenzene derivatives, higher reaction temperatures were required for the exchange reactions to proceed completely.

Contributions of hop-derived thiols were examined. Extremely strong fruity, black currant-like aromas were detected in beers hopped with some U.S. cultivars. 4-Mercapto-4-methylpentan-2-one (4MMP) was supposed to be the main contributor to the fruity aroma, and the contents between cultivars were investigated. In hop pellets, a negative correlation between 4MMP concentration and copper ion content in hops was observed. 4MMP was detected only in U.S., Australian, and New Zealand cultivars, but no European ones, which are treated with copper-containing fungicides (Bordeaux mixture) and therefore have a high content of copper ions. The 4MMP content was highest in Simcoe cultivars, followed by Summit, Apollo, Topaz, Cascade pellets, and also differed between crop years. It was indicated that most 4MMP exists freely in wort or in hop pellets with only small amounts formed from precursors and that the amounts increased during the fermentation process.