514-95-4Relevant academic research and scientific papers
Synthetic studies on breviones: Construction of the CDE ring system
Takikawa, Hirosato,Hirooka, Manabu,Sasaki, Mitsuru
, p. 1713 - 1716 (2007/10/03)
Breviones A-E (1-5), allelopathic agents isolated from Penicillium brevicompactum Dierckx, are structurally unique pentacyclic or hexacyclic diterpenoid derivatives. The synthesis of a structurally simplified model compound (8), corresponding to the chara
Reaction of cyclic allylic acetates with aliphatic alcohols in the presence of cerium(III) chloride
Uzarewicz,Dresler
, p. 1921 - 1930 (2007/10/03)
The reactions of selected allylic acetates with methanol, ethanol, n-propyl alcohol, isopropyl alcohol and tert-butyl alcohol in the presence of catalytic amounts of cerium(III) chloride are described. Allylic alkyl ethers, bis-allylic ethers and 1,3-dienes were obtained depending on the structure of the acetates.
Reaction of allylic alcohols with aliphatic alcohols in the presence of cerium(III) chloride. Part II
Uzarewicz,Dresler,Scianowski
, p. 710 - 718 (2007/10/03)
The reactions of selected allylic alcohols with methanol, ethanol, n-propanol, isopropanol and tert-butanol in the presence of catalytic amounts of cerium(III) chloride are described. Allylic alkyl ethers, bis-allylic ethers and 1,3-dienes were obtained d
The reaction of cyclic allylic alcohols with aliphatic alcohols in the presence of cerium(III) chloride
Uzarewicz,Dresler
, p. 181 - 195 (2007/10/03)
Cyclic secondary and tertiary allylic alcohols react with primary aliphatic alcohols in the presence of cerium(III) chloride heptahydrate to give alkyl allylic ethers. When secondary or tertiary aliphatic alcohols are used 1,3-dienes are obtained from allylic alcohols heaving the 3-methyl-2-en-1-ol moiety (3-8, 13-15).
Synthesis of Alkyl Allylic Ethers and 1,3-Dienes by the Reaction of Conjugated Cyclohexenones with Sodium Borohydride-Cerium(III) Chloride in Aliphatic Alcohols
Uzarewicz, A.,Dresler, R.
, p. 1655 - 1658 (2007/10/03)
The reaction of conjugated cyclohexenones 1,3-containing 3-methyl-2-en-1-one moiety with NaBH4/CeCl3*7H2O in primary aliphatic alcohols (MeOH, EtOH, n-PrOH) affords alkyl allylic ethers and 1,3-dienes.In isopropanol or tert-butanol only 1,3-dienes are obtained.Ketones 4-6 containing 2-methyl-2-en-1-one moiety are reduced under the same conditions to the corresponding allylic alcohols irrespective of the alcohol used.Key words: reduction, α,β-unsaturated ketones, allylic alcohols, alkyl allylic ethers, sodium borohydride, cerium(III) chloride
Structure-Odor Correlation, VII. - Synthesis and Olfactive Properties of Theaspirane Analogues
Weyerstahl, Peter,Buchmann, Bernd,Marschall-Weyerstahl, Helga
, p. 507 - 524 (2007/10/02)
The spirodihydrofurans 8-12 were prepared by addition of the respective alkynols to the ketone 20 (-->21-25), Lindlar hydrogenation (-->26-30), and cyclization. - The saturated derivatives 1-6 were available either by hydrogenation (8-10-->1,2,4) or via the lactol 47 and its reaction to the diols 31-36.Addition of the ethyl acetate anion to 20 (-->71), reduction (71-->73), and cyclization yielded the spirooxetane 13. - From the ynediols 76 and 77, Lindlar hydrogenation (-->78,79), cyclization (-->80,81), and further hydrogenation led to the spirotetrahydropyranes 16and 17. - Key compound for the synthesis of the ketone 18 was the geranic acid derivative 94, which could be obtained in two different ways.Cyclization of 94 to the diester 92 and Dieckmann condensation of 92 under simultaneous methylation (-->99) led to 18.The diastereoisomers 18a and b could be assigned after reduction of 18 to the separable alcohols 19a-c. - The olfactive properties (strength and quality) of the theaspirane analogues are determined by the conformational flexibility of the respective molecule.Thus, the almost rigid 13 has a very strong camphoraceous-herbaceous odor.Augmenting flexibility, particularly by increasing of the ring size (-->1,-->16), but also by alkyl substitution at C-2, results in remarkably weaker, woody-flowery notes.
Cyclic terpenoid onium salts, their preparation and uses
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, (2008/06/13)
Acyclic terpenoid onium salts are cyclized in an acidic aqueous solution at a temperature of at least about 80° C.
