title: Synthesis of 1,3,6-Trisubstituted Azulenes.
abstract: We have developed a short, general synthetic route to 1,3,6-trisubstituted azulenes. The key intermediate, 6-methylazulene, was synthesized from readily available and inexpensive starting materials in 63% yield over two steps. The methyl group of 6-methylazulene was then used as a synthetic handle to introduce different substituents at the 6-position via two different methods. Subsequently, the 1- and 3-positions were substituted with additional functional handles, such as formyl, chloromethylketone, and iodide. The efficiency of the synthetic route was demonstrated by preparing a collection of three different products with the best demonstrated yield 33% over seven steps.
authors.affiliation: Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki , Viikinkaari 5 E, FI-00014 Helsinki, Finland.
authors.forename: Teppo O
authors.initials: TO
authors.lastname: Leino
authors.affiliation: Department of Chemistry, Durham University , South Road, Durham DH1 3LE, United Kingdom.
authors.forename: Marcus
authors.initials: M
authors.lastname: Baumann
authors.affiliation: Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki , Viikinkaari 5 E, FI-00014 Helsinki, Finland.
authors.forename: Jari
authors.initials: J
authors.lastname: Yli-Kauhaluoma
authors.affiliation: Department of Chemistry, Durham University , South Road, Durham DH1 3LE, United Kingdom.
authors.forename: Ian R
authors.initials: IR
authors.lastname: Baxendale
authors.affiliation: Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki , Viikinkaari 5 E, FI-00014 Helsinki, Finland.
authors.forename: Erik A A
authors.initials: EA
authors.lastname: Wallén