554-61-0Relevant articles and documents
AN INVESTIGATION OF TERPENE HYDROCARBONS OF THE CARANE SERIES BY PHOTOELECTRON SPECTROSCOPY
Chuiko, V. A.,Manukov, E. N.,Chukhov, Yu. V.,Timoshenko, M. M.
, p. 600 - 605 (1985)
2- and 3-Carenes and carane have been studied by PE spectroscopy.On the basis of an analysis of orbital interactions and information obtained from the PE spectra of model compounds an assignment has been made of the bands corresponding to ionization from the molecular orbitals of the double bond and of the cyclopropane ring.
Solvent-free isomerization of 3-carene to 2-carene using Na/o-chlorotoluene catalyst in trans-isolimonene production
Julianto, Tatang Shabur,Jumina,Jojo, Hardjono Sastrohamid,Mustofa
, p. 3107 - 3111 (2018/01/17)
Trans-isolimonene is one of the important compound in drugs development. This compound can be made by isomerization of inexpensive 3-carene via 2-carene using Na/o-chlorotoluene catalyst in xylene. The existence of xylene as a solvent requires a further separation process that can reduce the efficiency when applied in the bulk industry. The isomerization of 3-carene to 2-carene has been studied in solvent free reaction compared by isomerization without xylene solvent. The result showed that the isomerization can also occur in solvent-free condition. Solventfree isomerization gave 27.72% of conversion and 83.27% of selectivity while isomerization with solvent gave 23.59% of conversion and 86.87% of selectivity.
Ruthenium containing hydrotalcite as a solid base catalyst for >C{double bond, long}C< double bond isomerization in perfumery chemicals
Sharma, Sumeet K.,Parikh, Parimal A.,Jasra, Raksh V.
experimental part, p. 27 - 33 (2010/04/28)
Ruthenium containing hydrotalcite (Ru-Mg-Al) is used as a solid base catalyst for >C{double bond, long}C2 and Ru-alumina for isomerization of methyl chavicol to trans-anethole. Ru-Mg-Al catalyst was reused four times without loss in its activity, however, significant loss in the conversion of methyl chavicol and selectivity of trans-anethole was observed on reusability of other ruthenium impregnated catalysts. The conversion of methyl chavicol and selectivity of trans-anethole was found to increase on increasing the reaction temperature as well as amount of catalyst. At 0.005 g catalyst amount, 55% conversion of methyl chavicol with 68% selectivity of trans-anethole was observed that increased to 93% with 82% selectivity of trans-anethole at 0.05 g catalyst amount. On further increase in the amount of catalyst to 1 g, conversion increased to 98% with 88% selectivity of trans-anethole.
Platinum- and gold-catalyzed rearrangement reactions of propargyl acetates: Total syntheses of (-)-α-cubebene, (-)-cubebol, sesquicarene and related terpenes
Fuerstner, Alois,Hannen, Peter
, p. 3006 - 3019 (2008/02/04)
Propargyl acetates, in the presence of catalytic amounts of late transition-metal salts such as PtCl2 or AuCl3, represent synthetic equivalents of α-diazoketones. This notion is corroborated by a concise approach to various sesquiterpene natural products starting from readily available substrates. Specifically, (+)-carvomenthone (17) is converted into propargyl acetate (S)-26 by a sequence involving Stille cross-coupling of its kinetic enol triflate 18, regioselective hydroboration/oxidation of the resulting 1,3-diene 19, and addition of an alkynyl cerium reagent to aldehyde 21 thus obtained. Since the latter step was found to be unselective, the configuration of the reacting propargyl acetate was unambiguously set by oxidation followed by diastereoselective transfer hydrogenation by using Noyori's catalyst 25. Compound (5)-26, on treatment with PtCl2 in toluene, converted exclusively to the tricyclic enol acetate 27, which was sap onified to give norcubebone 11 in excellent overall yield. The conversion of this compound into the sesquiterpene alcohol (-)-cubebol (6) was best achieved with MeCeCl2 as the nucleophile, whereas the formation-of the parent hydrocarbon (-)-α-cubebene (4) was effected in excellent yield by recourse to iron-catalyzed cross coupling methodology developed in this laboratory. Since norketone 11 has previously been transformed into (-)-β-cubebene (5) as well as (-)-4-epicubebol 8, our approach constitutes formal total syntheses of these additional natural products as well. Along similar lines, the readily available propargyl acetates 1, 33 and 47 were shown to give access to 2-carene 44, sesquicarene 39, and episesquicarene 51 in excellent overall yields. In this series, however, the cy cloisomerization reaction was best achieved with catalytic amounts of AuCl3 in 1,2-dichloroethane as the solvent. In addition to these preparative results, our data provide some insight into the mechanism of these remarkable skeletal rearrangement reactions. Transformations of this type are likely triggered by initial coordination of the alkyne unit of the substrate to the carbophilic transition-metal cation. Formal attack of the alkene moiety onto the resulting π-complex engenders the formation of an electrophilic cyclopropyl carbene species which subsequently reacts with the adjacent acetate unit to give the final product. The alternative phasing of events, implying initial attack of the acetate (rather than the alkene moiety) onto the metal-alkyne complex, is inconsistent with the stereochemioal data obtained during this total synthesis campaign.
Intramolecular cyclopropanation reactions of organozinc carbenoids derived from terpenoid enals
Motherwell, William B.,Roberts
, p. 1121 - 1124 (2007/10/02)
Treatment of a series of unsaturated terpenoid enals with 1,2 bis (chlorodimethylsilyl) ethane and zinc provides a simple and efficient method for intramolecular cyclopropanation.
TRANSFORMATIONS OF 4-HYDROXYMETHYL-2-CARENE OVER POTASSIUM HYDROXIDE
Manukov, E. N.,Vyglazov, O. G.,Chuiko, V. A.,Shingel', I. A.
, p. 1912 - 1914 (2007/10/02)
The dehydration of 4-hydroxymethyl-2-carene over potassium hydroxide at 250 deg C, which leads to the formation of 4-methyl-3(10),4-caradiene and 3,4,7,7-tetramethyl-1,3,5-cycloheptatriene, was investigated.The dehydration is accompanied by a small degree
DISPROPORTIONATION OF HYDROGEN IN 3-CARENE
Manukov, E. N.,Chuiko, V. A.,Vyglazov, O. G.
, p. 257 - 262 (2007/10/02)
The disproportionation of hydrogen in 3-carene takes place with the formation of compounds of the 1,1,4-trimethylcycloheptane series.The proposed reaction mechanism involves dehydration of the 2-carene to 2,4-caradiene, which exists in a rapid tautomeric equilibrium with 3,7,7-trimethyl-1,3,5-cycloheptatriene.This gives rise to the appearance of compounds with a seven-membered ring in the reaction product.
Liquid Crystalline Catalysis, 3, Monomolecular Rearrangements of Terpene Derivatives in Liquid Crystalline Solvents
Melone, S.,Mosini, V.,Nicoletti, R.,Samori, B.,Torquati, G.
, p. 399 - 410 (2007/10/02)
The ability of limonene and linalool to rearrange in mesomorphic media is apparently determined by the constraints exerted by the solvent structure on the translational diffusions of the reactant solute molecules.Selective conversions seem to be promoted by the different media.Alkylcyclohexyl- and alkylbicyclohexyl-carboxylic acids and their mixtures with toluic acid have been used as solvents.The B structure of their smectic phases has been demonstrated by X-ray diffraction studies.
HETEROGENEOUS HYDROGENATION OF 3,7,7-TRIMETHYLCYCLOHEPTA-1,3,5-TRIENE
Manukov, E. N.,Chuiko, V. A.
, p. 422 - 425 (2007/10/02)
It has been shown that the intermediate products of the hydrogenation of 3,7,7-trimethylcyclohepta-1,3,5-triene on platinum black are 2- and 3-carenes, in addition to olefins and dienes of the 1,1,4-trimethylcycloheptane series.The final hydrogenation products contains 96percent of 1,1,4-trimethylcycloheptane and 4percent of carenes.
