Isolongifolene ketones

Isolongifolene ketone exo CAS 29461-14-1 EINECS/ELINCS 249-649-3 Synonyms 2a,4aa,8a-Hexahydro-1,1,5,5-tetramethyl-2H-2,4a-methanonaphthalen-8(5H)-one... 

Ketosesquine. See Isolongifolene ketone exo 1-3-Ketothreohexuronic acid lactone. SeeL-Ascorbic acid... 

Hops (Humulus lupulus) oil Isodonis japonicus extract Isoeugenol Isolongifolene ketone exo Isopentylcyclohexanone Isopropylphenylbutanal Juniperus communis oil Linalyl acetate Linseed (Linum usitassimum) extract Lovage (Levisticum officinale) extract... 

Isolongifolene ketone exo Ketosesquine 29548-30-9 Famesyl acetate 29586-23-6 Copper abietate 29590-42-9 Isooctyl acrylate SR 440 29598-76-3... 

Isolongifolene ketone exo Ketosesquine 249-689-1 Famesyl acetate 249-707-8 Isooctyl acrylate SR 440 249-793-7 Crodamol OHS Dermol 00 Estalan 718 Estalan OV Kessco DHS Naturechem OHS Norfox 171 Octyl hydroxystearate Schercemol OHS Wickenol 171 249-794-2 Cetyl caprylate 249-818-1 Diisodecyl qlutarate 249-862-1 Bernel Ester EHP Cegesoft C 24 Cegesoft C 25 Ceraphyl 368 Crodamol OP Elfacos EHP Estalan 816 Estalan-OP Estol 1543 Estol EHP-b 3652 Exceparl EH-P HallStar OP Jeechem OP Kessco EHP Lexol EHP Liponate EHP Octyl palmitate... 

Fujioka, H. Regio- and stereoselective rearrangement reactions of various a,/ -e poxy acy-lates suitable combination of acyl groups and Lewis acids. Tetrahedron 1999, 55, 4979—4998. Ravikumar, K. S. Begue, J.-P. Bonnet-Delpon, D. Ourevitch, M. Synthesis in fluorous phase a convenient synthesis of isolongifolene epoxide and its rearrangement to a ketone. J. Fluorine Chem. 2000, 102, 51-53. 

The synthesis of the tricyclic enone (237) has been reported (Scheme 35). The carbonyl group has previously been removed from this ketone to produce isolongifolene. The key step in this synthesis is the facile intramolecular y-alkylation of the keto-tosylate (236). 

Attempted peroxy acid epoxidation of the bicyclic ketone (31 equation 13) gave the lactone (33), instead of several possible rational alternatives. The epoxide (32) was implicated as an intermediate when it was independently synthesized from the epoxy alcohol, and shown to give (33) on treatment with aqueous acid.- A mechanism involving scission of the acyl bridgehead bond via the hydrated 1,1 -diol form of the ketone was proposed to account for the formation of this unexpected product. The rearrangement of the isolongifolene derivative (34 equation 14) appears to be mechanistically related. The product (35) is formed by brief treatment with dilute HCIO4 in dioxane as a mixture of isomers believed to arise by acid-catalyzed epimerization of the carbinol center. ... 

If oxidation of isolongifolene with perbenzoic add is carried out in chloroform solution, almost two mole equivalents of the rea nt are consumed, an experience reminiscent of the uncontrolled peracid oxidation of longifolene. The main product of the reaction was shown to be the lactone (197) while interruption of the reaction at one mole equivalent consumption led, as expected, to the isolation of the ketone (198) (33). Extrapolating the longifolene-peracid chemistry to the present case, SuKH Dev et al. (30) prepared the primary product of oxidation, the epoxide (199), by carrying out the reaction in benzene solution. In this case also, it is the facility with which isomerization of the oxide to the carbonyl derivative occurs as the result of steric compression, which causes further uptake of peracid. 

Amongst miscellaneous intramolecular reactions noted have been intramolecular alkylation of an a,j8-unsaturated ketone at the 7-position [synthesis of ( )-isolongifolene] and an application of intramolecular diyl trapping to the synthesis of linearly fused tricyclopentanoids. The key step in the last example is illustrated from compound (50) it is expected to have utility in syntheses of various natural products. 

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