105-87-3Relevant articles and documents
Facile syntheses of [8,9-2H2]- and [8-2H]-digeranyl
Nakagawa, Osamu,Shimoda, Kei,Izumi, Shunsuke,Hirata, Toshifumi
, p. 1301 - 1309 (2000)
[8,9-2H2]- and [8-2H]-(2E,6E,10E,14E)-2,6,11,15-tetramethyl-2,6,10,14-hexadecatetraene (digeranyl) (1 and 2) have been synthesized from geraniol by the condensation of geranyl p-tolylsulfone and reductive desulfonylation in the key steps.
Highly selective oxidation of allylic alcohols to α,β-unsaturated aldehydes using Pd cluster catalysts in the presence of molecular oxygen
Kaneda, Kiyotomi,Fujii, Masanori,Morioka, Kengo
, p. 4502 - 4503 (1996)
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Alcoholyses and acetolyses of allylic and tertiary benzylic alcohols catalyzed by 2,3-dichloro-5,6-dicyanobenzoquinone
Iranpoor,Mottaghinejad
, p. 2253 - 2260 (1995)
Allylic and tertiary benzylic alcohols can be converted into their corresponding ethers and acetates selectively and efficiently in the presence of catalytic amounts of 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ).
Photoacylation of alcohols in neutral medium
Debieux, Jean-Luc,Cosandey, Anne,Helgen, Celine,Bochet, Christian G.
, p. 2073 - 2077 (2007)
We report here conditions which allow the photoacylation of primary, secondary and tertiary alcohols with N-acetyl-5,7-dinitroindoline under exceptionally mild conditions, at wavelengths harmless to most functional groups, including otherwise photosensitive ones. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
Synthetic applications of homoiodo allylsilane II. Total syntheses of (-)-andrographolide and (+)-rostratone
Gao, Hai-Tao,Wang, Bian-Lin,Li, Wei-Dong Z.
, p. 9436 - 9448 (2014)
The first total synthesis of (-)-andrographolide (1), an ent-Labdane diterpenoid lactone from Asian medicinal herb Andrographis paniculata, was achieved via the biomimetic cyclization of an epoxy homoiodo allylsilane precursor 7. Asymmetric total synthesis of (+)-rostratone (25), an antipodal Labdane diterpenoid, was also accomplished via similar biomimetic cyclization of a readily accessible epoxy homoiodo allylsilane precursor 18.
Continuous-Flow Chemo and Enzymatic Synthesis of Monoterpenic Esters with Integrated Purification
Adarme, Carlos A.A.,Le?o, Raquel A.C.,de Souza, Stefania P.,Itabaiana, Ivaldo,de Souza, Rodrigo O.M.A.,Rezende, Claudia M.
, p. 39 - 46 (2018)
Monoterpenic esters are very important flavor and fragrance compounds due to their organoleptic properties. Despite their importance, many drawbacks are found for the production of monoterpenic esters. Here in we report two different approach's (chemo and enzymatic) for the continuous production of monoterpenic esters with integrated purification arriving on the desired molecules with high yields (>95%) and short reaction times.
Synergistic factors ensue high expediency in the synthesis of menaquinone [K2] analogue MK-6: Application to access an efficient one-pot protocol to MK-9
Yerramsetti, Nanaji,Dampanaboina, Lavanya,Mendu, Venugopal,Battula, Satyanarayana
, (2020)
Here we report a practical and efficient method for the synthesis of menaquinone vitamin (K2) analog MK-6 in all trans forms through “1 + 5 convergent synthetic approach” of pentaprenyl chloride with monoprenyl menadione derivative. In the synergistic factors, less efficient leaving group/more efficient nucleophile (Cl) in the substrate makes it more prominent reaction by eliminating all Sn2’ side reaction products. Further, the addition of acetic acid in the last step (desulfonation) of reaction sequence removes the limitations of the reactions in terms of cyclized side product (multiple reactions of pentaprenyl alcohol with Et3B), byproduct (Et3B, incendiary compound) formations and their interruption in the tricky purification processes. The utility of this method was further extended to find an efficient one-pot synthesis to MK-9 to the gram scale synthesis. This approach is economical and efficient and avoids the awkward chromatographic separation processes.
Unravelling transition metal-catalyzed terpenic alcohol esterification: A straightforward process for the synthesis of fragrances
Da Silva,Ayala
, p. 3197 - 3207 (2016)
Iron nitrate is a simple and commercially available Lewis acid and is demonstrated to be able to catalyze β-citronellol esterification with acetic acid, achieving high conversion and ester selectivity (ca. 80 and 70%, respectively), within shorter reaction times than those reported in the literature. To the best of our knowledge, this is the first report of a terpenic alcohol esterification reaction catalyzed by Fe(NO3)3. This process is an attractive alternative to the slow and expensive enzymatic processes commonly used in terpenic alcohol esterification. Moreover, it avoids the undesirable steps of neutralizing the products, which are always required in mineral acid-catalyzed reactions. We have performed a study of the activity of different metal Lewis acid catalysts, and found that their efficiency is directly linked to the ability of the metal cation to generate H+ ions from acetic acid ionization. The measurement of pH as well as the conversions achieved in the reactions allowed us to obtain the following trend: Fe(NO3)3 > Al(NO3)3 > Cu(NO3)2 > Ni(NO3)2 > Zn(NO3)2 > Mn(NO3)2 > Co(NO3)2 > LiNO3. The first three are recognized as stronger Lewis acids and they generate more acidic solutions. When we carried out reactions with different iron salts, it was possible to conclude that the type of anion affects the solubility of the catalyst, as well as the conversion and selectivity of the process. Fe2(SO4)3 and FeSO4 were insoluble and less active. Conversely, though they were equally soluble, Fe(NO3)3 was more selective for the formation of β-citronellyl acetate than FeCl3. We assessed the effects of the main reaction variables such as reactant stoichiometry, temperature, and catalyst concentration. In addition to citronellol, we investigated the efficiency of the iron(iii) catalyst in the solvent free esterification of several terpenic alcohols (geraniol, nerol, linalool, α-terpineol) as well as other carboxylic acids.
Total Synthesis of Isohericenone J via a Stille Coupling Reaction
Cao, Wei,Chen, Ping,Tang, Yu
, p. 1701 - 1705 (2020)
The first total synthesis of isohericenone J is reported. Key features of this synthetic strategy are a Friedel-Crafts reaction to construct the isobenzofuranone unit and a Pd-catalyzed Stille coupling reaction for the formation of the C5-C1′ bond, generating the natural product, as well as one of its isomers, in 6.0% overall yield in eight steps. This strategy provides a foundation for the synthesis of challenging isobenzofuranone and isoindolinone-type derivatives.
Identification of presumed pheromone blend from Australasian predaceous bug, Oechalia schellenbergii (Heteroptera: Pentatomidae)
Aldrich, Jeffrey R.,Oliver, James E.,Waite, Geoff K.,Moore, Chris,Waters, Rolland M.
, p. 729 - 738 (1996)
Oechalia schellenbergii is one of the most common predatory insects in Australia and the islands of the South Pacific. Adult males of this predaceous "true bug" collected during March near Gatton, Queensland, Australia, had a pair of enlarged exocrine glands opening underneath their wings that presumably produce an artractant pheromone. The two major components of the secretion are 3-methylenehexyl acetate and 9-hydroxygeranyl diacetate [2,6-dimethyl-2(E),6(E)-octadien-1,8-diol diacetate].
Design, synthesis, and biological evaluation of new (2E,6E)-10-(dimethylamino)-3,7-dimethyl-2,6-decadien-1-ol ethers as inhibitors of human and Trypanosoma cruzi oxidosqualene cyclase
Galli, Ubaldina,Oliaro-Bosso, Simonetta,Taramino, Silvia,Venegoni, Serena,Pastore, Emanuele,Tron, Gian Cesare,Balliano, Gianni,Viola, Franca,Sorba, Giovanni
, p. 220 - 224 (2007)
New dimethylamino truncated squalene ether derivatives containing a different aromatic moiety (phenyl, naphthyl, and biphenyl) or a simple alkyl (n-hexylic) group were synthesized as inhibitors of the oxidosqualene cyclase (OSC) and of the sterol biosynthetic pathway. The activity against human OSC was compared with the activity against the OSCs of pathogenic organisms such as Pneumocystis carinii and Trypanosoma cruzi. The phenyl derivative was the most potent inhibitor of T. cruzi OSC.
Isomerisation cis trans regioselective de doubles liaisons trisubstituees.
Cuvigny,Herve du Penhoat,Julia
, p. 1331 - 1334 (1980)
At moderate temperatures aqueous sulphur dioxide equilibrates trisubstituted double bonds.
Selective allylic hydroxylation of acyclic terpenoids by CYP154E1 from Thermobifida fusca YX
Bogazkaya, Anna M.,Von Buehler, Clemens J.,Kriening, Sebastian,Busch, Alexandrine,Seifert, Alexander,Pleiss, Juergen,Laschat, Sabine,Urlacher, Vlada B.
, p. 1347 - 1353 (2014)
Allylic alcohols are valuable precursors in the synthesis of pharmaceutical intermediates, agrochemicals and natural products. Regioselective oxidation of parental alkenes is a challenging task for chemical catalysts and requires several steps including protection and deprotection. Many cytochrome P450 enzymes are known to catalyse selective allylic hydroxylation under mild conditions. Here, we describe CYP154E1 from Thermobifida fusca YX that enables this type of oxidation. Several acyclic terpenoids were tested as possible substrates for CYP154E1, and the regio- and chemoselectivity of their oxidation was investigated. Using a previously established bioinformatics approach we identified position 286 in the active site of CYP154E1 which is putatively involved in substrate binding and thereby might have an effect on enzyme selectivity. To tune regio- and chemoselectivity of the enzyme three mutants at position 286 were constructed and used for substrate oxidation. All formed products were analysed with GC-MS and identified using chemically synthesised authentic samples and known compounds as references. Best regioselectivity towards geraniol and nerol was observed with the wild type enzyme mainly leading to 8-hydroxy derivatives (8-hydroxygeraniol or 8-hydroxynerol) with high selectivity (100% and 96% respectively). Highest selectivities during the oxidation of geranylacetone and nerylacetone were observed with the following variants: V286F led mainly to 7-hydroxygeranylacetone (60% of the total product) and V286A produced predominantly 12-hydroxynerylacetone (75% of total product). Thus, CYP154E1 and its mutants expand the tool-box for allylic hydroxylation in synthetic chemistry.
Synthesis of Cembranoid Analogues through Ring-Closing Metathesis of Terpenoid Precursors: A Challenge Regarding Ring-Size Selectivity
Heidt, Tanja,Baro, Angelika,K?hn, Andreas,Laschat, Sabine
, p. 12396 - 12404 (2015)
A systematic study on ring-closing metathesis with Grubbs II catalyst to cembranoid macrocycles is described. Acyclic terpenoids with a functional group X in the homoallylic position relative to an RCM active terminus and substituents R, R1 directly attached to the other terminal double bond were prepared from geraniol derived trienes and fragments that are based on bromoalkenes and dimethyl malonate. Such terpenoids were suitable precursors, despite the presence of competing double bonds in their framework. The size of R and R1 is crucial for successful macrocyclization. Whereas small alkyl substituents at the double bond directed the RCM towards six-membered ring formation, cross metathesis leading to dimers dominated for bulkier alkyl groups. A similar result was obtained for precursors without functional group X. In the case of unsymmetrically substituted terpenoid precursor (R=Et, R1=Me) with homoallylic OTBS or OMe group, the RCM could be controlled towards formation of macrocyclic cembranoids, which were isolated with excellent E-selectivity. The role of the substituents was further studied by quantum chemical calculations of simplified model substrates. Based on these results a mechanistic rationale is proposed.
BAKER'S YEAST HYDROGENATION OF CARBONYL ACTIVATED DOUBLE BONDS. ENANTIOSELECTIVE SYNTHESIS OF THE (S) -FORM OF THE DIHYDROTERPENEDIOL SECRETED BY DANAUS CHRYSIPPUS AND OF A PHEROMONE OF CALLOSOBRUCHUS CHINENSIS L.
Gramatica, Paola,Giardina, Giuseppe,Speranza, Giovanna,Manitto, Paolo
, p. 1395 - 1398 (1985)
The (S)- forms of (E)-3,7-dimethyl-2-octene-1,8-diol (secreted by male danaid butterflies) and of (E)-3,7-dimethyl-2-octene-1,8-dioic acid (a pheromone of the azuki bean weevil) were synthesized via stereoselective hydrogenation by baker's yeast of the carbonyl activated double bond of achiral precursors.
Iridoid Sex Pheromone Biosynthesis in Aphids Mimics Iridoid-Producing Plants
Partridge, Suzanne J.,Withall, David M.,Caulfield, John C.,Pickett, John A.,Stockman, Robert A.,Oldham, Neil J.,Birkett, Michael A.
, p. 7231 - 7234 (2021)
Biosynthesis of (1R,4aS,7S,7aR)-nepetalactol (1) and (4aS,7S,7aR)-nepetalactone (2) in plants involves iridoid synthase (ISY), an atypical reductive cyclase that catalyses the reduction of 8-oxogeranial into the reactive enol of (S)-8-oxocitronellal, and cyclization of this enol intermediate, either non-enzymatically or by a nepetalactol-related short chain dehydrogenase enzyme (NEPS) that yields the nepetalactols. In this study, we investigated the biosynthesis in vivo of 1 and 2 in the pea aphid, Acyrthosiphon pisum, using a library of isotopically-labelled monoterpenoids as molecular probes. Topical application of deuterium-labelled probes synthesized from geraniol and nerol resulted in production of 2H4?lactol 1 and 2H4?lactone 2. However, deuterium incorporation was not evident using labelled probes synthesized from (S)-citronellol. These results suggest that iridoid biosynthesis in animals, specifically aphids, may follow a broadly similar route to that characterised for plants.
Molybdenum-modified mesoporous SiO2as an efficient Lewis acid catalyst for the acetylation of alcohols
Hlatshwayo, Xolani S.,Ndolomingo, Matumuene Joe,Bingwa, Ndzondelelo,Meijboom, Reinout
, p. 16468 - 16477 (2021/05/19)
A suitable, expeditious and well-organized approach for the acetylation of alcohols with acetic anhydride in the presence of 5%MoO3-SiO2 as an optimum environmentally benign heterogeneous catalyst was developed. The high surface area obtained for 5%MoO3-SiO2, 101 m2 g-1 compared to other catalysts, 22, 23, and 44 m2 g-1 for 5%WO3-ZrO2, 5%WO3-SiO2, and 5%MoO3-ZrO2, respectively, appears to be the driving force for better catalytic activity. Amongst the two dopants used, molybdenum oxide is the better dopant compared to its tungsten oxide counterpart. High yields of up to 86% were obtained with MoO3 doping while WO3 containing catalysts did not show any activity. Other reaction parameters such as reactor stirring speed, and solvent variation were studied and revealed that the optimum stirring speed is 400 rpm and cyclohexane is the best solvent. Thus, the utilization of affordable and nontoxic materials, short reaction times, reusability, and producibility of excellent yields of the desired products are the advantages of this procedure.
Synthesis method of geranyl acetate
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Paragraph 0078-0103; 0108-0115, (2020/11/01)
The invention relates to the technical field of preparation of flavors and fragrances, in particular to a synthesis method of geranyl acetate. The synthesis method of geranyl acetate comprises the following steps of: mixing acetic acid, geraniol and a polymerization inhibitor, heating the mixture to 60-140 DEG C, then adding a catalyst, and starting stirring; detecting the content of acetic acid in the reaction solution every 20-60 minutes, and stopping the reaction when the content of acetic acid is stable. According to the synthesis method of geranyl acetate, cation exchange resin is used asa catalyst, the catalytic activity and selectivity are excellent, other side reactions are not found, the reaction liquid is basically colorless, and geranyl acetate obtained through purification islighter in color and luster than geranyl acetate obtained through catalysis of concentrated sulfuric acid. Meanwhile, the catalytic system provided by the invention has the advantages of easiness in separation from a product, small corrosion to equipment, no environmental pollution, reusability and the like.
