Total Synthesis of Dihydroclerodin from (R)-(−)-Carvone
摘要:
The first total synthesis of the natural enantiomer of the insect-antifeedant dihydroclerodin (1) and lupulin C (40) has been achieved starting from (R)-(-)-carvone (2). In the applied strategy, the hexahydrofuro[2,3-b]furan moiety was introduced in an early stage of the synthesis. The correct configuration at C-9, C-11, C-13, and C-16 was established by application of a remarkably diastereoselective Mukaiyama reaction. The desired configuration at C-10 was obtained by catalytic reduction of the intermediate enone 21. After annulation of the second ring, the structural features at C-4, C-5, and C-6 were introduced. The successful finishing of the synthesis included a Chugaev elimination to give the exocyclic double bond at C-4 that is present in lupulin C. Oxidation of this double bond with m-CPBA afforded dihydroclerodin.
Enantioselective Synthesis of Functionalised Decalones by Robinson Annulation of Substituted Cyclohexanones, Derived from R-(−)-Carvone
作者:Ben J.M Jansen、Cindy C.J Hendrikx、Nikolai Masalov、Gerrit A Stork、Tommi M Meulemans、Fliur Z Macaev、Aede de Groot
DOI:10.1016/s0040-4020(00)00110-1
日期:2000.3
catalysed conjugate addition of methyl magnesium iodide to cyclohexenones and trapping of the enolate as its trimethylsilyl enol ether, followed by a trityl hexachloroantimonate (TrSbCl6) catalysed Mukaiyama-reaction, was applied to R-(−)-carvone. This proved to be an efficient method for the preparation of C-2, C-3 functionalised chiral cyclohexanones. These compounds were converted into their α-cyano ketones
Enantioselective synthesis of highly functionalised cyclohexanones starting from R-(−)-carvone
作者:Tommi M. Meulemans、Gerrit A. Stork、Ben J.M. Jansen、Aede de Groot
DOI:10.1016/s0040-4039(98)01367-7
日期:1998.9
Copper (I) catalysed conjugateaddition of methylmagnesium iodide to R-(−)-carvone and trapping the enolate as its trimethylsilyl enol ether, followed by a trityl perchlorate (TrClO4) catalysed Mukaiyama-aldol reaction, is an efficient method for the preparation of highly functionalised cyclohexanones which can be used as starting compounds in the total syntheses of enantiomerically pure clerodanes