DE73089C - Process for the preparation of a new odoriferous substance from citral, called Jonon - Google Patents

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CLASS 12: Chemical apparatus and processes.

Patented in the German Empire on April 35, 1893.

It was found that citral and acetone. condense to a ketone composed according to the formula C ₁₃ H ₂₀ O if a mixture of these two compounds is subjected to the action of alkaline earth metal hydrates or alkali metal hydrates or other alkaline agents for a sufficiently long time in the presence of water.

The ketone formed from citral and acetone under these conditions is said to be pseudojonone called.

This compound can, for example, be obtained by shaking equal parts by weight of citral and acetone with a solution of barythydrate for several days, then taking up the reaction products in ether, and subjecting the residue remaining when the ether is evaporated to fractional distillation under reduced pressure. You start the mm under 12 pressure at 138-155 ^0-boiling fraction and drives it unangegriffenes citral, unchanged retarded acetone and volatile Condensations- ■ producte of the latter from the vapor stream. The oil remaining in the still is boiled over in the air-diluted room.

The pseudo-ionon formed, which is a ketone easily decomposable by alkaline agents, boils under 12 mm pressure at 143 to 145 °, has, as already noted, the formula C ₁₃ H ₂₀ O, a volume weight of 0.904 and a refraction exponent JVd = 1.537.

The pseudo-jonon has a peculiar but not very pronounced odor; it. Like most of the higher molecular ketones, it no longer combines with sodium bisulfite, but otherwise shows the characteristic properties of the ketones and delivers like these with phenylhydrazine, hydroxylamine, and other ammonia substituted condensation products.

The pseudo-jonon, the smell of which in and of itself is of no importance for perfumery appears to be used as the starting material for making a compound with an extremely characteristic odor. Namely, it goes thinner under the influence Acids into an isomeric ketone called ionone.

This conversion can e.g. B. be effected by heating 20 parts of pseudo-ionone with 100 parts of water, 2.5 parts of sulfuric acid and 100 parts of glycerine in an oil bath to the boiling point of this mixture for several hours. It is taken up in ether to the Reactionsproduct, the ether evaporated and the residue is fractionated in the air space diluted by the catches 12 mm under pressure at 125 to 135 ⁰ Fraction boiling. The ionone thus prepared can be further purified by converting it with phenylhydrazine or other substituted ammonia into a ketone condensation product which can be decomposed again by dilute acids. The ketone

. Edition, issued on g. January igoi.J

condensation products of the pseudo-ion with phenylhydrazine and other ammonia derivatives can initially be converted by acids into ketone condensation products of the ion will.

The ionone has the formula C ₁₃ H ₂₀ O, boils around 128 ⁰ under 12 mm pressure, has a volume weight of 0.935 and a refraction exponent of Nd = 1.507.

The Jonon has a fresh floral scent, which is reminiscent of the scent of violets and at the same time somewhat reminiscent of the smell of the vine blossoms.

Hydroiodic acid converts the ionone at a higher temperature with elimination of water into a _{hydrocarbon composed according to the formula C 13} / Z ₁₈ , which boils under 12 min pressure at 106 to 112 ⁰ and through strong oxidizing agents into an acid of the formula C _{12 which} ^{melts at 214 0} / Z _{1 a} O _{n is} converted.

Claims (1)

Patent claim: Process for the preparation of a new odorous substance made from citral and called Jonon Acetone, consisting in the fact that the two compounds mentioned are replaced by alkaline ones The agendas begin with a new ketone, the pseudo-jonon, condensed and the pseudo-jonon or its condensation products with phenylhydrazine or other ammonia derivatives by acids into a ketone isomeric with the pseudo-ionone, the actual ionone, convicted.