105-90-8Relevant articles and documents
Enzymatic modification of palmarosa essential oil: Chemical analysis and olfactory evaluation of acylated products
Ramilijaona, Jade,Raynaud, Elsa,Bouhlel, Charfeddine,Sarrazin, Elise,Fernandez, Xavier,Antoniotti, Sylvain
, p. 2291 - 2301 (2013)
We have developed an enzymatic protocol to modify the composition of palmarosa essential oil by acylation of its alcohol components by three different acyl donors at various rates. The resulting modified products were characterized by qualitative and quantitative analyses by gas chromatography, and their olfactory properties were evaluated by professional perfumers. We showed that our protocol resulted in two types of modifications of the olfactory properties. The first and most obvious effect observed was the decrease of the alcohol content, with the concomitant increase of the corresponding esters, along with their fruity notes (pear, most notably). The second and less obvious effect was the expression of notes from minor components ((E)-β-ocimene, linalool, β-caryophyllene, and farnesene), originally masked by the sweet-floral-rose odor of geraniol, present in 70% in the palmarosa essential oil used, and emergence of citrus, green, spicy and clove characters in the modified products. This methodology might be considered in the future as a sustainable route to new natural ingredients for the perfumer. Copyright
In situ immobilization of Candida antarctica B lipase in polyurethane foam support
Nyari, Nadia Ligianara D.,Fernandes, Ilizandra A.,Bustamante-Vargas, Cindy E.,Steffens, Clarisse,De Oliveira, Débora,Zeni, Jamile,Rigo, Elisandra,Dallago, Rogério M.
, p. 52 - 61 (2016)
Candida antarctica B (CALB) lipase was immobilized using polyurethane (PU) foam as support by confinement method. This can be a promising technique due to the low cost of the support, simple procedure of immobilization and the possibility of using the derivative as catalyst for the food industry reactions. CALB immobilization on PU was performed using 6 mL polyol and 4 mL isocyanate (60-40%, v/v), with 1 mL of enzymatic solution (0.8 g enzyme in 5 mL distilled water). The immobilization process resulted in a 535% increase in activity for the enzymatic derivative. The enzyme was stable for 360 days at room (10-25 °C) and low (2-8 °C) temperatures, for 300 days at 40 and 60 °C and for 150 days at 80 °C in wet ambient conditions. The synthesis of geranyl propionate and ethyl oleate catalyzed by the immobilized derivative presented conversions of around 97 and 83%, respectively. The immobilized CALB in PU was reused consecutively different behavior occurred which stored in dry ambient conditions at different temperatures (room: 10-25 °C, refrigeration: 2-8 °C and 40 °C) resisted 30 cycles, for both forms of storage, keeping more than 87, 95 and 83% of its activity, respectively.
Efficient Enzymatic Preparation of Flavor Esters in Water
Perdomo, Igor Chiarelli,Gianolio, Stefania,Pinto, Andrea,Romano, Diego,Contente, Martina Letizia,Paradisi, Francesca,Molinari, Francesco
, p. 6517 - 6522 (2019/06/20)
A straightforward biocatalytic method for the enzymatic preparation of different flavor esters starting from primary alcohols (e.g., isoamyl, n-hexyl, geranyl, cinnamyl, 2-phenethyl, and benzyl alcohols) and naturally available ethyl esters (e.g., formate, acetate, propionate, and butyrate) was developed. The biotransformations are catalyzed by an acyltransferase from Mycobacterium smegmatis (MsAcT) and proceeded with excellent yields (80-97%) and short reaction times (30-120 min), even when high substrate concentrations (up to 0.5 M) were used. This enzymatic strategy represents an efficient alternative to the application of lipases in organic solvents and a significant improvement compared with already known methods in terms of reduced use of organic solvents, paving the way to sustainable and efficient preparation of natural flavoring agents.
Formyloxyacetoxyphenylmethane and 1,1-diacylals as versatile O-formylating and O-acylating reagents for alcohols
Chapman, Robert S.L.,Francis, Molly,Lawrence, Ruth,Tibbetts, Joshua D.,Bull, Steven D.
, p. 6442 - 6452 (2018/10/02)
Formyloxyacetoxyphenylmethane, symmetric 1,1-diacylals and mixed 1-pivaloxy-1-acyloxy-1-phenylmethanes have been used as moisture stable O-formylating and O-acylating reagents for primary and secondary alcohols, allylic alcohols and phenols under solvent/catalyst free conditions to afford their corresponding esters in good yield.
An examination of the scope and stereochemistry of the Ireland-Claisen rearrangement of boron ketene acetals
Seizert, Curtis A.,Ferreira, Eric M.
supporting information, p. 4460 - 4468 (2014/05/06)
The Ireland-Claisen rearrangement of boron ketene acetals is described. The boron ketene acetal intermediates are formed through a soft enolization that obviates the use of strong bases and the intermediacy of alkali metal enolates. Yields and diastereoselectivities of these rearrangements are very sensitive to the choice of boron reagent, even among those that have been shown to effect quantitative formation of boron ketene acetals from esters. The rearrangement occurs at room temperature for all substrates with generally high levels of stereoselectivity. In contrast to previous reports using boron triflates, the use of a commercially available boron iodide reagent allows for a wider substrate scope that extends to propionates and arylacetates, as well as the previously described α-oxygenated esters. This work also provides insight into the dynamic nature of boron ketene acetals and the ramifications of this behavior for reactions in which they are intermediates. Borane down: Boron enolates of allylic esters are efficiently generated at -78 °C using cHx2BI (dicyclohexyliodoborane)·Et3N. These rearrange smoothly on being warmed to room temperature to give generally high diastereoselectivity in forming γ,δ-unsaturated acids (see scheme). The rearrangements provide a key insight into the dynamic nature of boron ketene acetals.
A clean enzymatic process for producing flavour esters by direct esterification in switchable ionic liquid/solid phases
Lozano, Pedro,Bernal, Juana M.,Navarro, Alicia
, p. 3026 - 3033 (2013/01/15)
A clean biocatalytic approach for producing flavour esters using switchable ionic liquid/solid phases as reaction/separation media has been developed. The phase behaviour of different IL/flavour acetyl ester (geranyl acetate, citronellyl acetate, neryl acetate and isoamyl acetate) mixtures was studied at several concentrations, resulting for all cases in fully homogeneous liquid media at 50 °C, and solid systems at room temperature. By using an iterative centrifugation protocol on the solid IL/flavour ester mixtures at controlled temperatures, the solid IL phase and the liquid flavour ester phase can be easily separated. The excellent suitability of an immobilized Candida antarctica lipase B (Novozym 435) catalyst in the esterification reaction between an aliphatic carboxylic acid (acetic, propionic, butyric or valeric) and a flavour alcohol (isoamyl alcohol, nerol, citronellol or geraniol) in N,N′,N′′,N′′′-hexadecyltrimethyl-ammonium bis(trifluoromethylsulfonyl)imide ([C16tma][NTf2])IL has been demonstrated, the product yield being improved up to 100% under appropriate reaction conditions (enzyme amount, dehydrating molecular sieves, etc.) at 50 °C. The enzymatic synthesis of sixteen different flavour esters was carried out in [C16tma][NTf2] by means of this approach, providing products of up to 0.757 g mL-1 concentration after IL separation. The residual activity of the enzyme/IL system during seven consecutive operation cycles was shown to be practically unchanged after reuse.
PROCESSES FOR SYNTHESIZING ESTERS BY 1,4-ADDITION OF ALKANOIC ACIDS TO MYRCENE OR ISOPRENE
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Page/Page column 15-16, (2008/06/13)
Processes are disclosed for synthesizing esters useful in flavorings and fragrances from ?-pinene, myrcene and/or isoprene. The esters can be used in the manufacture of citral, precursors to citral and other products or precursors such as vitamins, nutritional supplements, flavorings, fragrances and other products. The process includes a 1,4-addition of an alkanoic acid to the conjugated diene of myrcene (which can be generated from ?-pinene) or the conjugated diene of isoprene to produce esters thereof.
Toward a total synthesis of brassinosteroids; structure assessment of the Ireland-Claisen products of geranyl and neryl esters
Temmem,Uguen,De Cian,Gruber
, p. 3169 - 3173 (2007/10/03)
As estimated by 1H NMR analysis, thermal isomerisation of the kinetic silylenolate derived from the ester (Z)-8a proceeds with acceptable diastereo and facial selectivity, thence affording an acid having the required absolute configuration for further elaboration to brassinosteroids.
OZONOLYSIS OF ALKENES AND REACTIONS OF POLYFUNCTIONAL COMPOUNDS. XLIX. SYNTHESIS OF THE CHLORINE DERIVATIVES OF ACYLPRENOLS
Odinokov, V. N.,Kukovinets, O. S.,Sakharova, N. I.,Tolstikov, G. A.
, p. 1057 - 1060 (2007/10/02)
The chlorine derivatives of acylprenols with a terminal isopropenyl group were obtained by the action of sulfuryl chloride on the products from ozonolysis of 1,5,9-trimethyl-(1E,5E,9E)-cyclododecatriene.
