The present invention is directed to a process for the manufacture of 1,1,4,4-tetramethoxy-2-butene from 2,5-dimethoxy-2,5-dihydrofuran with methanol in the presence of an acidic ion exchanger as catalyst, whereby the molar ratio of 2,5-dimethoxy-2,5-dihydrofuran to methanol is ≥1:45. The present invention is further directed to a process of separating 1,1,4,4-tetramethoxy-2-butene, methanol and 2,5-dimethoxy-2,5-dihydrofuran from each other and H2O whereby a basic compound, preferably a basic metal salt or a basic ion exchanger, is present. Both processes can be carried out on an industrial scale, batch-wise or in continuous mode and are sustainable since the selectivity and the space-time-yields are high and less waste compared to known processes is produced. Further objects of the present invention are the use of a basic compound in the distillation of a mixture comprising H2O, 1,1,4,4-tetramethoxy-2-butene and 2,5-dimethoxy-2,5-dihydrofuran, as well as the use of an acidic ion exchanger as catalyst in a reaction of 2,5-dimethoxy-2,5-dihydrofuran with methanol to 1,1,4,4-tetramethoxy-2-butene, whereby the molar ratio of 2,5-dimethoxy-2,5-dihydrofuran to methanol is ≥1:45.

Provided are a terminal conjugated trienal acetal compound useful as an intermediate for producing a terminal conjugated trienal compound, and a method for producing a terminal conjugated trienal compound through deprotection of the terminal conjugated trienal acetal compound. More specifically, provided are a terminal conjugated trienal acetal compound represented by General Formula (1); a method for producing a (Z,E)-terminal conjugated trienal acetal compound, the method comprising the step of: reacting a phosphonium salt represented by General Formula (7) with (E)-2,4-pentadienal through Wittig reaction to obtain a (Z,E)-terminal conjugated trienal acetal compound represented by General Formula (3); and a method for producing a terminal conjugated trienal compound, the method comprising the step of: deprotecting the terminal conjugated trienal acetal compound represented by General Formula (1) to obtain a terminal conjugated trienal compound represented by General Formula (2).

##STR00001##

Provided are a terminal conjugated trienal acetal compound useful as an intermediate for producing a terminal conjugated trienal compound, and a method for producing a terminal conjugated trienal compound through deprotection of the terminal conjugated trienal acetal compound. More specifically, provided are a terminal conjugated trienal acetal compound represented by General Formula (1); a method for producing a (Z,E)-terminal conjugated trienal acetal compound, the method comprising the step of: reacting a phosphonium salt represented by General Formula (7) with (E)-2,4-pentadienal through Wittig reaction to obtain a (Z,E)-terminal conjugated trienal acetal compound represented by General Formula (3); and a method for producing a terminal conjugated trienal compound, the method comprising the step of: deprotecting the terminal conjugated trienal acetal compound represented by General Formula (1) to obtain a terminal conjugated trienal compound represented by General Formula (2).

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The present invention relates to the field of perfumery. More particularly, it concerns valuable new chemical intermediates for producing perfuming ingredients. Moreover, the present invention also comprises a process for producing compound of formula (I).

##STR00001##

The present invention relates to the field of perfumery. More particularly, it concerns valuable new chemical intermediates for producing perfuming ingredients. Moreover, the present invention also comprises a process for producing compound of formula (I).

##STR00001##

The present disclosure provides a device for continuously preparing 2,6-dihydroxybenzaldehyde and use thereof. The device includes a first continuous reaction unit for hydroxy protection reaction, a second continuous reaction unit for lithiation and hydroformylation, and a third continuous reaction unit for deprotection reaction that are connected in series. The third continuous reaction unit includes: a first columnar continuous reactor, connected to the second continuous reaction unit and used for deprotection of the lithiated hydroformylated product while performing liquid separation to obtain an organic phase containing 2,6-dihydroxybenzaldehyde and an aqueous phase. When the device is applied in the preparation of 2,6-dihydroxybenzaldehyde, reaction time is shortened and the intermediate purification treatment is no longer required. Therefore, compared with batch process, the present disclosure can greatly save equipment cost and post-processing cost, and greatly improve the production efficiency, more beneficial to the industrial scale-up production of 2,6-dihydroxybenzaldehyde.

The present disclosure provides a device for continuously preparing 2,6-dihydroxybenzaldehyde and use thereof. The device includes a first continuous reaction unit for hydroxy protection reaction, a second continuous reaction unit for lithiation and hydroformylation, and a third continuous reaction unit for deprotection reaction that are connected in series. The third continuous reaction unit includes: a first columnar continuous reactor, connected to the second continuous reaction unit and used for deprotection of the lithiated hydroformylated product while performing liquid separation to obtain an organic phase containing 2,6-dihydroxybenzaldehyde and an aqueous phase. When the device is applied in the preparation of 2,6-dihydroxybenzaldehyde, reaction time is shortened and the intermediate purification treatment is no longer required. Therefore, compared with batch process, the present disclosure can greatly save equipment cost and post-processing cost, and greatly improve the production efficiency, more beneficial to the industrial scale-up production of 2,6-dihydroxybenzaldehyde.

The present disclosure provides a device for continuously preparing 2,6-dihydroxybenzaldehyde and use thereof. The device includes a first continuous reaction unit for hydroxy protection reaction, a second continuous reaction unit for lithiation and hydroformylation, and a third continuous reaction unit for deprotection reaction that are connected in series. The third continuous reaction unit includes: a first columnar continuous reactor, connected to the second continuous reaction unit and used for deprotection of the lithiated hydroformylated product while performing liquid separation to obtain an organic phase containing 2,6-dihydroxybenzaldehyde and an aqueous phase. When the device is applied in the preparation of 2,6-dihydroxybenzaldehyde, reaction time is shortened and the intermediate purification treatment is no longer required. Therefore, compared with batch process, the present disclosure can greatly save equipment cost and post-processing cost, and greatly improve the production efficiency, more beneficial to the industrial scale-up production of 2,6-dihydroxybenzaldehyde.

The present invention relates to new odorous acetals which are useful as fragrance or flavor materials in particular in providing vanilla and spicy notes with a natural impression resembling vanilla absolute.

The present invention relates to new odorous acetals which are useful as fragrance or flavor materials in particular in providing vanilla and spicy notes with a natural impression resembling vanilla absolute.