Alpha-pinene and beta-pinene are abundantly represented in nature; they are obtained from renewable sources and are irreplaceable synthons for commercial-scale production of other terpenes. In a well-known process practiced by Millennium Specialty Chemicals (MSC), hydrogenation of pinenes gives cis- and trans-pinanes, which are oxidized to hydroperoxides, whose reduction gives cis- and trans-pinanols, respectively. Pyrolysis of the pinanols gives linalool. Industrial availability of the pinanols makes them attractive objects for further synthetic research. We found that, in a very simple process of 'chlorooxidation', cis- and trans-pinanols react with hypochloric acid producing a novel chloroketone 1-[3-(2-chloroethyl)-2,2-dimethylcyclobutyl]ethanone and a tricyclic ether 6,9-dimethyl-7-oxatricyclo[4.3.0.0(3,9)]nonane, respectively. Both compounds offer new broad synthetic opportunities, providing access to numerous dimethylcyclobutane derivatives and to C(9)-functionalized pinenes and pinanes. The chlorooxidation reaction was also extended to other terpene alcohols such as dihydroplinol, tetrahydromyrcenol, and tetrahydrolinalool. This review, based on a presentation at the RSC/SCI conference Flavours & Fragrances 2007 in London, September 24-26, 2007, will touch on environmental issues related to pinenes, give a brief overview of the existing pinene-based technologies, and discuss the new experimental results.

The preparation of some new thiophene and thianaphthene dyes and their derivatives has been presented and discussed. The absorption spectra of 3-Thianaphthene Malachite Green, 2-Thianaphthene Malachite Green and its derivatives, 3-Thiophene Malachite Green and its derivatives have been determined and compared with the absorption spectra of Malachite Green. An interpretation of the bathochromic effects of the thiophene and thianaphthene rings in triarylmethane dyes has been offered.

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