Selective oxidations of dienone 2 as well as a ring‐closing metathesis to give the hydroazulene framework enabled the 12‐step preparation of title compound 1 from (−)‐photocitral A (3), which is in turn rapidly available from (−)‐isopulegol through dual catalysis.
The synthesis of (+)‐orientalol F (1) started with aldehyde 6, which is available from (R)‐limonene in two steps. Wittig reaction of 6 with unsaturated ylide 7 to give a tetraene, and subsequent ring‐closing metathesis yielded hydroazulene 4, selective epoxidation of which gave epoxy ester 3. After generation of the requisite isopropyl unit and regioselective reductive epoxide opening, the derived dienol 2 was used for the installation of the oxygen bridge through intramolecular oxymercuration followed by oxidative demercuration. The resulting allylic alcohol epimers 15 and 16 were readily converted into the target natural product 1 by oxidation/reduction sequences.
Selektive Oxidationen des Dienons 2 sowie eine Ringschlussmetathese zum Hydroazulengerüst ermöglichten die 12‐stufige Synthese der Titelverbindung 1 aus (−)‐Photocitral A (3), das seinerseits rasch mittels dualer Katalyse aus (−)‐Isopulegol erhältlich ist.
Summary(−)-Oxyphyllol was prepared in only 4 steps from an epoxy enone that already served as an intermediate for the total synthesis of the anticancer guaiane (−)-englerin A. A regio- and diastereoselective Co(II)-catalyzed hydration of the olefin and a transannular epoxide opening were used as the key reactions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.