- Chemical plants: High-value molecules from essential oils
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As society faces a future of dwindling petrochemical supplies at increasing cost, much attention has been focused on methods to degrade biomass into renewable commodity-chemical building blocks. Reported here is a powerful complementary approach that amplifies the complexity of molecular structures present in plant materials. Essential-oil phenylpropenoids are transformed via acrylate cross-metathesis into potent antioxidants that are widely used in perfumery and cosmetics, and in treating disorders associated with oxidative damage.
- Lummiss, Justin A. M.,Oliveira, Kelley C.,Pranckevicius, Alexandre M. T.,Santos, Alexandra G.,Dos Santos, Eduardo N.,Fogg, Deryn E.
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- Tandem catalysis: Versus one-pot catalysis: Ensuring process orthogonality in the transformation of essential-oil phenylpropenoids into high-value products via olefin isomerization-metathesis
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Conversion of essential-oil allylbenzenes (phenylpropenoids) to high-value fine chemicals via isomerization-metathesis is reported. The target reaction sequence involves isomerization of ArCH2CH=CH21 into the corresponding conjugated olefins 2, and ensuing cross-metathesis with acrylates to generate ArCH=CHCO2R 3. The second-generation Hoveyda catalyst HII was chosen for the metathesis step. A range of lead candidates was assessed for the isomerization step, of which most active was the Grotjahn catalyst [CpRu(PN)(MeCN)]PF6([4]PF6; PN = 2-PiPr2-4-tBu-1-Me-imidazole). The following order of isomerization activity was determined, using the isomerization of estragole 1a to anethole 2a (Ar = p-MeOC6H4) as a probe reaction: [CpRu(PN)(MeCN)]PF6> RuHCl(CO)(PPh3)3> Ru(Me-allyl)2(COD) > Pd2Br2(PtBu3)2> RuHCl(PPh3)3> RuCl3(μ2-C)(μ2,κ1-C,η6-Mes-H2IMes)Ru(H)(H2IMes) (the "Grubbs hydride") > RuHCl(CO)(H2IMes)(PCy3) > RuHCl(CO)(IMes)(PCy3) > RuHCl(CO)(PCy3)2. To maximize process efficiency, a systematic comparison of orthogonal tandem catalysis versus sequential catalyst addition was undertaken, using catalysts [4]PF6and HII. The impact of each process type on product selectivity and catalyst compatibility was assessed. Selectivity was undermined in tandem isomerization-metathesis by competing metathesis of 1. Sequential catalyst addition eliminated this problem. The isomerization catalyst [4]PF6adversely affected metathesis yields when equimolar with HII, an effect traced to the imidazole functionality in [4]PF6. However, at the low catalyst loadings required for efficient isomerization (0.1 mol% [4]PF6), negligible impact on metathesis yields was evident. The target cinnamates and ferrulates were obtained in quantitative yields by coupling these steps in a one-pot isomerization-metathesis protocol.
- Higman, Carolyn S.,De Araujo,Fogg, Deryn E.
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- Highly efficient synthesis of an emerging lipophilic antioxidant: 2-ethylhexyl ferulate
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Ferulic acid in ester form has shown a stronger ability in ameliorating certain pathological conditions and inhibiting lipid oxidation. In present study, a solvent-free and reduced pressure evaporation system was developed for lipase-catalyzed synthesis o
- Huang, Kuo-Chuan,Li, Ying,Kuo, Chia-Hung,Twu, Yawo-Kuo,Shieh, Chwen-Jen
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- METHOD FOR PRODUCING CINNAMIC ACID ESTER COMPOUND
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A method for producing a cinnamic acid ester derivative includes reacting a cinnamic acid derivative compound represented by the formula (1), wherein the symbols are as defined in the description, with an alcohol compound represented by the formula: R6OH, wherein the symbol is as defined in the description, in the presence of a strong acid resin catalyst without using a solvent. As the cinnamic acid derivative compound, cinnamic acid, ferulic acid, and caffeic acid are preferred, and as the alcohol compound, methanol, ethanol, propanol, butanol, pentanol, hexanol, ethylene glycol, glycerol, phenethyl alcohol, and a monosaccharide are preferred.
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Paragraph 0066-0067; 0070; 0075
(2020/05/06)
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- Solvent-free lipase-catalyzed preparation of long-chain alkyl phenylpropanoates and phenylpropyl alkanoates
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An enzymatic method was developed for the preparation of medium- or long-chain alkyl 3-phenylpropenoates (alkyl cinnamates), particularly alkyl hydroxy- and methoxy-substituted cinnamates such as oleyl p-coumarate and oleyl ferulate. The various alkyl cin
- Vosmann, Klaus,Weitkamp, Petra,Weber, Nikolaus
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p. 2969 - 2976
(2007/10/03)
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- Ferulic acid ester antioxidant/UV absorbent
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An antioxidant/UV absorbent useful in cosmetics is formed of an ester of ferulic acid with an alkanol having 1 to 12 carbon atoms.
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