- A synthetic route to 4-alkyl-α-methylhydrocinnamylaldehydes
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The 4-Alkyl-α-methylhydrocinnamylaldehydes (alkyl-isopropyl, isobutyl, methyl) are frequently used fragrances with desired floral (lilac, cyclamen, lily-of-the-valley) scent. These substances are valued for their good stability in basic solution and, therefore, are frequently used in soaps, detergents, or shampoos. These substances are synthesized by a two-step synthesis involving base catalyzed aldol condensation of 4-alkylbenzaldehyde with propanal followed by selective hydrogenation of the C=C bond. In aldol condensation, selectivity is decreased by formation of undesired products of propanal autocondensation 2-methylpent-2-enal. In this work the reaction conditions for homogenous catalyzed aldol condensation of 4-isobutylbenzadehyde with propanal were tested (catalyst type and amount, molar ratio of reactants, solvent type). Reaction conditions giving the best results (92% conversion, 79% selectivity) were adapted to other 4-alkyl-α-methylcinnamylaldehydes preparation with similar results. In the second step—hydrogenation of aldol product different types of catalyst (nickel, cobalt, palladium or Adkins catalyst), and also different solvents, were tested. Hydrogenation conditions leading to the highest yield (72% selectivity at 95% conversion) were adapted to other 4-alkylhydrocinnamyladehydes with similar results.
- Vrbková, Eva,Vysko?ilová, Eli?ka,Rott, Martin,Zapletal, Martin,?erveny, Libor
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p. 2603 - 2613
(2017/03/22)
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- Synthesis method of silver aldehyde spice
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The invention discloses a synthesis method of a silver aldehyde spice and relates to the technical field of fine chemical engineering. Isobutyl benzene and propionyl chloride are used as starting raw materials, silver aldehyde is synthesized through acylation reaction and hydrodechlorination, the raw materials in use are easy to obtain, and the product yield is high. Ethyl alcohol serves as an organic solvent for hydrogenation reaction, the shortcomings of incomplete reaction or excessive hydrogenation and inactivation after mechanical application of a catalyst in the hydrogenation process are overcome, the content of meta-position silver aldehyde and ortho-position silver aldehyde during side reaction is controlled to be 0.5% or below, the content of 2-methyl-3(4-(2-methyl propyl) phenyl) propyl alcohol in a silver aldehyde finished product is controlled to be 0.5% or below, the unimodal content of the silver aldehyde product can be 98.5% or above, and the silver aldehyde spice has a pure and soft aroma and meets the flavoring requirements of essences and spices.
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Paragraph 0064-0072; 0089-0097
(2017/02/24)
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- LILIAN SURROGATE
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Due to toxicological concerns, it may be desirable to replace the fragrance compound lilial with less problematic compounds without losing the creative power and quality regarding perfumes. The present invention addresses this need by using selected oxazolidines described herein.
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- Perfumes
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A substantially odourless aromatic amine trapping agent is used in a composition including perfume for the purpose of enabling the perfume and trapping agent to react chemically together spontaneously and reversibly to form a reaction product form which the perfume can be released. In the reaction product, the perfume may be protected against degradation, premature evaporation etc., with the perfume being releasable from the reaction product. In contrast to a pro-perfume, the reaction product formed the present invention is not used by being included as such in a mixture of perfumes or perfumed product, but instead the perfume and trapping agent are included in a mixture of perfumes or perfumed product where they react spontaneously in situ to form a transient reaction product for subsequent release of the perfume. The invention also provides a perfume composition including the trapping agent.
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