CS198325B1 - Process for preparing alkylcinnamylethers and alkyl/phenylallyl/-ethers - Google Patents

Description

These disadvantages are overcome by the process of the present invention, which comprises treating 4-phenyl-1,3-dioxane with hydrochloric acid in the presence of ammonium chloride, and then separating the resulting cinnamyl chloride as an organic layer which, upon addition of alcohol, and the basic catalyst is processed to the corresponding alkylsinnamyl ether or a mixture of alkylcinnamyl ether and alkyl (phenylallyl) ether. When an alkali hydroxide is used as the basic catalyst, the end product is alkylcmamylettier, using alkali carbonate to form a mixture of alkylcinnamyl ethers and alkyl (phenylallyl) ether.

The basic effect of the process according to the invention is to substantially increase the yield of the substances.

The procedure is explained in more detail in the following examples of a specific embodiment.

Example 1

To a 2 L two-necked flask equipped with a stirrer, thermometer, and reflux condenser was added 160 mL of water, 107 g (2 mol) of ammonium chloride, 300 mL (2 mol) of 4-phenyl-1,3-dioxane and 320 mL (3.84). The mixture was kept under stirring for 1 h at 100 ° C using a temperature controlled oil bath, then the stirring was turned off and the layers were hot spun off The lower aqueous layer containing formaldehyde, hydrochloric acid, chloride ammonium chloride and a mixture of the imine and amine hydrochlorides formed by the reaction of formaldehyde with ammonium chloride and hydrochloric acid were separated, and 160 ml of water, 107 g of ammonium chloride and 320 ml of 37% hydrochloric acid were added to the organic layer. Then the lower aqueous layer was separated and to the organic layer was added 128 g (4 mol) of methanol and with stirring over 30 min 80 g (2 mol) of solid sodium chloride. The mixture was spontaneously heated and after reaching 50 ° C, the reaction flask was cooled with water so as to maintain a slight reflux. The reaction mixture was held for 1 hour. After cooling to room temperature, 300 ml of water was added to the mixture, and the mixture was neutralized with 45 ml (0.54 mol) of concentrated hydrochloric acid. The lower aqueous layer was separated and the upper organic layer was subjected to vacuum distillation. 171 g of 1-phenyl-3-methogy-1-propene (cinnamyl methyl ether) of m.p. 104 DEG-105 DEG C. at 1.87 kPa were obtained, representing a 58% yield on 4-phenyl-1,3-dioxane.

Example 2

Other alkylcinnamyl ethers were prepared in an analogous manner to Example 1, wherein the alkyls were ethyl, propyl, isopropyl, allyl, butyl, isobutyl, sec-butyl, n-amyl, isoamyl, 2-ethyl-1-hexyl and 3-phenyl-1. -propyl. Yields ranged from 45 to 90% on 4-phenyl-1,3-dioxane.

Example 3

The procedure was carried out as in Example 1, except that after separating the second aqueous layer, 593 g (18.5 mol) of methanol and 159 g (1.5 mol) of anhydrous sodium carbonate were added to the organic layer. After cooling at room temperature, carbonate and sodium chloride were filtered off, methanol was distilled off in a vacuum evaporator, and 166 g of a mixture containing 35% of 1-phenyl-3-methoxy-1 were obtained by vacuum distillation. -propene (cinnamyl ether at 104-105 ° C at 1.87 kPA) and 65% 3-phenyl-3-methoxy-1-propane (methylphenylallyl ether) at 75-75.5 ° C at 1, 87 kPa), which represents a 56% yield of an ether mixture to 4-phenyl-1,3-dioxane, which can be used as such or separated by distillation into both components.

Example 4

In an analogous manner to Example 3, mixtures of alkylcinnamyl and alkyl (phenylallyl) ethers were prepared in which the alkyls were the same as in Example 2. The yields of the ether mixture ranged from 45 to 90% on 4-phenyl-1,3-dioxane.

Claims (3)

SUBJECT A process for the preparation of alkylcinnamyl ethers and alkyl (phenylallyl) ethers, wherein the alkyl contains 1 to 9 carbon atoms, characterized in that the 4-phenyl-1,3-dioxane is treated with hydrochloric acid in the presence of ammonium chloride, and then formed The cinnamyl chloride is separated in the form of an organic layer which, after addition of the alcohol and the basic catalyst, is processed to the corresponding alkylcinnamyl ether or a mixture of alkylcinnamyl ether and alkyl (phenylallyl) ether. 2. The process of claim 1 wherein the basic catalyst is an alkali hydroxide. 3. The process of claim 1 wherein the basic catalyst is an alkali carbonate.