CS241283B1 - Process for preparing guaetholallyl ether - Google Patents

Abstract

The method of preparing guaethol allyl ether consists in reacting allyl halide with sodium salt of guaethol in a molar ratio of up to 2:1 in the presence of a phase transfer catalyst based on a quaternary ammonium salt in an inert solvent environment at temperatures of 70 to 130 °C. Guaethol allyl ether is used in the fragrance industry.

Description

Process for preparing guaetholallyl ether

The process for preparing guaetholallyletber is based on guaethole sodium

Allyl halide is present in a molar ratio of up to 2: 1 in the presence of a quaternary ammonium salt phase transfer catalyst in an inert solvent environment at temperatures of 70 to 130 ° C.

Guaetholallylether finds use in the fragrance industry.

241 283

- SL 241 283

The invention relates to a process for the preparation of guaetholallyl ether. It is mainly used in the fragrance industry. Its fragrant properties are characterized as a natural, warm, spicy fragrance complex with a wooden end reminiscent of cloves and guaiacol oil. The substance is available on the market. The production process has not been found in the literature.

Suitable starting materials for the synthesis of guaetholallyl ether appear to be guaethol. its alkali salt and allyl halide, preferably allyl bromide or allyl chloride in analogy to the known preparation of pyrocatechin monoallyl ether from pyrocatechin sodium in the reaction mixture described in Laskina D.V., Děvické T.A. and Běliova V.N. in Chimia and the technology of souvenir hangings and efferent butter IV., 51 (1965). None of the attempts to similarly prepare guaetholallyl ether from guaethol sodium directly in the reaction mixture led to the target.

The way guaetholallylether was prepared was i

The process according to the invention, characterized in that the sodium salt of guaethol is treated with an allyl halide in a molar ratio of 1 to 2: 1 in the presence of a phase transfer catalyst based on a quaternary ammonium salt, preferably triethylbenzylammonium chloride _from an inert solvent, e.g. toluene, at temperatures of 70 to 150 ° C.

The specific embodiment is apparent from the following examples.

Example 1

A 2 liter flask was charged with 1000 ml of toluene, 20 g of finely chopped sodium and 60 g of guaethole. The mixture was stirred

241,283 hours at room temperature. The resulting sodium salt was separated, washed 13 times with 600 ml of toluene heated to 40-60 ° C. The final eluate contained no free guaethole (as determined by gas chromatography). 77.6 g of theor was obtained. the sodium salt of guaethol with which further synthesis was performed. To a stirred flask equipped with a reflux condenser, a thermometer and a β side tube divider in a thermostated bath was added 1.5 moles of guaethol sodium, 38 moles of toluene, 0.1 moles of phase-triethylbenzylammonium chloride phase transfer catalyst and heated to 80 ° C. mol of allyl chloride. After 8 hours, 75¾ conversion of guaethol sodium to guaetholallyl ether was achieved, as determined by gas chromatography, which was no longer increased. The mixture was shaken with water, the toluene was evaporated and the guaetholallyl ether was separated by distillation / rt. 121 DEG C. (2.1 kPa). It was obtained in 62% yield.

Example 2

It was carried out analogously to Example 1 except that allyl bromide was used instead of allyl chloride ^ 75% conversion was achieved after 6 hours, otherwise the result was the same.

Example 3

It was carried out analogously to Example 1 except that a pressure apparatus was used to raise the reaction temperature to 130 ° C. The reaction time was reduced to 4 hours, otherwise the result was the same.

Claims (1)

OBJECT OF THE INVENTION _M 241 283 A process for the preparation of guaetholallyl ether, characterized in that the sodium salt of guaethol is treated with an allyl halide in a molar ratio of 1 to 2: 1 in the presence of a quaternary ammonium salt phase transfer catalyst in an inert solvent at 70 to 130 ° C.