There is provided a process for the preparation of a compound of formula (I) as defined herein, wherein said process comprises reacting a compound of formula (II) as defined s herein with one or more suitable Vilsmeier reagent.

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There is provided a process for the preparation of a compound of formula (I) as defined herein, wherein said process comprises reacting a compound of formula (II) as defined s herein with one or more suitable Vilsmeier reagent.

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The present invention relates to new malodour-counteracting agents of formula (I) or stereoisomers thereof, particularly useful in blocking the olfactory perception of androstenone, Formula (I), wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7 and X have the same meaning as that defined in the claims. The present invention also relates to consumer products comprising said agents. The present invention also relates to the use of said agents to suppress or attenuate undesirable odour, as well as to methods to suppress or attenuate undesirable odour employing said compounds.

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Disclosed is a method for preparing a material of plant origin rich in phenolic acids, including at least one metal, including: preparing a material of plant origin chosen from: aquatic plants; materials rich in tannins; materials rich in lignin; and obtaining a material of plant origin, rich in phenolic acids, in which the ratio of the intensity of the vibration band of the C═O bond of the COOH group and the intensity of each of the vibration bands the aromatic ring determined in FT-IR is between 0.5 and 4. The material of plant origin is brought into contact with an effluent including from 0.1 to 1000 mg/l of at least one metal, thus obtaining a material of plant origin rich in phenolic acids including from 1 to 30% by weight of at least one metal relative to the total weight of the material.

Disclosed is a method for preparing a material of plant origin rich in phenolic acids, including at least one metal, including: preparing a material of plant origin chosen from: aquatic plants; materials rich in tannins; materials rich in lignin; and obtaining a material of plant origin, rich in phenolic acids, in which the ratio of the intensity of the vibration band of the C═O bond of the COOH group and the intensity of each of the vibration bands the aromatic ring determined in FT-IR is between 0.5 and 4. The material of plant origin is brought into contact with an effluent including from 0.1 to 1000 mg/l of at least one metal, thus obtaining a material of plant origin rich in phenolic acids including from 1 to 30% by weight of at least one metal relative to the total weight of the material.

A compound is provided of Formula (I), wherein R.sup.1 represents a C.sub.3 to C.sub.20 hydrocarbon group derived from an alcohol of formula R.sup.1OH, from a formate of formula R.sup.1OCH═O, or a cinnamyl aldehyde of Formula (II) wherein a compound of Formula I is capable of releasing a compound, when oxidized, selected from the group consisting of a fragrant alcohol of formula R.sup.1OH, a fragrant formate ester of formula R.sup.1OCH=0 and aryl aldehyde of Formula (III), wherein R.sup.2 is, independently, hydrogen atom, hydroxyl group, optionally substituted C.sub.1-C.sub.6 alkyl group, C.sub.1-C.sub.6 alkoxy group, or -0(C=0)CH(CH3).sub.2 wherein any two of R.sup.2 may form an optionally substituted 5 or 6 membered ring. The compounds are useful for example as a precursor for the prolonged delivery or release of fragrant compounds such as fragrant alcohols, fragrant aldehydes or fragrant formates. ##STR00001##

A compound is provided of Formula (I), wherein R.sup.1 represents a C.sub.3 to C.sub.20 hydrocarbon group derived from an alcohol of formula R.sup.1OH, from a formate of formula R.sup.1OCH═O, or a cinnamyl aldehyde of Formula (II) wherein a compound of Formula I is capable of releasing a compound, when oxidized, selected from the group consisting of a fragrant alcohol of formula R.sup.1OH, a fragrant formate ester of formula R.sup.1OCH=0 and aryl aldehyde of Formula (III), wherein R.sup.2 is, independently, hydrogen atom, hydroxyl group, optionally substituted C.sub.1-C.sub.6 alkyl group, C.sub.1-C.sub.6 alkoxy group, or -0(C=0)CH(CH3).sub.2 wherein any two of R.sup.2 may form an optionally substituted 5 or 6 membered ring. The compounds are useful for example as a precursor for the prolonged delivery or release of fragrant compounds such as fragrant alcohols, fragrant aldehydes or fragrant formates. ##STR00001##

An efficient process useful for the self-condensation of aliphatic aldehydes is provided, catalyzed by dialkylammonium carboxylate salts. In particular, the invention provides a facile method for the preparation of 2-ethyl hexenal via the self-condensation of butyraldehyde using various dialkylammonium carboxylates, e.g., diisopropylammonium acetate or dimethylammonium acetate, as catalyst. Additionally, residual nitrogen arising from the catalyst can be reduced to −100 ppm levels in the product via a simple washing procedure. The invention provides a process for preparing alkenals under conditions which limit the formation of undesired impurities and high-boiling oligomeric substances.

An efficient process useful for the self-condensation of aliphatic aldehydes is provided, catalyzed by dialkylammonium carboxylate salts. In particular, the invention provides a facile method for the preparation of 2-ethyl hexenal via the self-condensation of butyraldehyde using various dialkylammonium carboxylates, e.g., diisopropylammonium acetate or dimethylammonium acetate, as catalyst. Additionally, residual nitrogen arising from the catalyst can be reduced to −100 ppm levels in the product via a simple washing procedure. The invention provides a process for preparing alkenals under conditions which limit the formation of undesired impurities and high-boiling oligomeric substances.

Disclosed is a method for preparing a solid material including manganese, the method including the following steps: a. bringing into contact an aqueous effluent including manganese, for example at least 5 mg/L, typically at least 5 to 50 mg/L, and preferably 7 to 25 mg/L of manganese, with an oxidizing agent, manganese, preferably at a temperature between 10° C. and 50° C., and obtaining an oxidized aqueous solution; b. adding a base to the oxidized aqueous solution obtained at the end of step a) until a pH of between 8 and 12, preferably greater than 9, and preferably from 9 to 10.5, and obtaining a solution including a precipitate; c. filtration of the solution obtained at the end of step b); and d. obtaining a solid material including manganese, and especially manganese (IV) and/or Mn (III).