PL167975B1 - Method for the preparation of new (E) -3,7-dimethyl-4-octene-1-alu derivatives - Google Patents

Abstract

A method for the preparation of new derivatives of (E)-3,7-dimethyl-4-octen-1-al of the general formula shown in the drawing, where n = 2 or 3, characterized in that (E)-3,7-dimethyl-4-octen-1-al is reacted with 1,2-ethanediol or 1,3-propanediol in the presence of catalytic amounts of p-toluenesulfonic acid or pyridinium p-toluenesulfonate.

Description

The subject of the invention is a process for the preparation of new (E) -3,7-dimethyl-4-octene-1-alu derivatives, with the general formula shown in the drawing, where n = 2 or 3.

The essence of the invention is that (E) -3,7-dimethyl-4-octene-1-al is reacted with 1,2-ethandiol or 1,3-propanediol in the presence of catalytic amounts of p-toluenesulfonic acid or p-toluenesulfonate pyridine.

The chemical compounds obtained according to the invention have attractive fragrance properties (the fragrance characteristics are listed in the table) and are used in the perfume industry as components of fragrance compositions.

The process according to the invention is explained in the preparation examples for 2- (2,6-dimethyl-3 (E) -heptene-1-yl) -1,3-dioxolane and 2- (2,6-dimethyl-3 (E) -heptene-1). -yl / -1,3-dioxane.

Example I. A mixture of 7.7 g (0.05 mol) of (E) -3.7-dimethyl-4-octene-1-alu, 3.7 g (0.06 mol) of ethylene glycol and 0.2 g (0.001 mol) p-toluenesulfonic acid or pyridinium p-toluenesulfonate in 300 cm ³ of toluene is heated to boiling, azeotropically distilling off the formed water of reaction. After 3 hours, the toluene solution was washed with saturated sodium carbonate solution and dried with anhydrous magnesium sulfate. After toluene evaporation, the residue is distilled under reduced pressure. As a result, 8.4 g of pure 2- (2,6-dimethyl-3 (E) -hepten-1-yl) -1,3-dioxolane are obtained, which is 85% of theory.

Example II. Proceeding in an analogous manner as in Example 1 to the reaction of 5.1 g (0.033 mol) of (E) -3.7-dimethyl-4-octene--1-alu and 3.2 g (0.042 mol) of 1,3-propanediol with using catalytic amounts of p-toluenesulfonic acid (0.15 g) or pyridine p-toluenesulfonate (0.2 g), 6.1 g of pure 2- (2,6-dimethyl-3 (E) -hepten-1-yl) -1 are obtained , 3-dioxane, 87% of theory.

The physical, spectral and aromatic properties of the compounds obtained are presented in the table.

Table

number groups methylene n Boiling point ° C / Pa 2 () n d 1N NMR (COC1, TMS) δ (ppm) IR (cm ' ¹ ) Fragrance characteristics 1 2 3 4 5 6 2 62-63 / 266 1.4428 0.86J = 5.9Hz, 6H, CH / CH3 / 2 /, 1.02 / d, J = 6.8 Hz, 3H, -CH / CH3 / - /, 2.35 / m, 1H, -CE / CH3 / - /, 3.75-4.0 (m, 4H, -OCH2CH2O-), 4.84 (t, J = 5.8 Hz, 1H, -CHCoO), 5.1-5.42 (m, 2H, -CH = CH-) 3040 / w / 1132 / s / 1040 / s / 972 / s / pleasant, medium intense, floral with a hint of fruit

167 975 the table continues

1 2 3 4 5 6 3 70-71 / 266 1, -4470 0.87 / d, J = 6 Hz, 6H-CH / CH3 / 2 /, 1.03 / d, J = 7 Hz, 3H, -CH / CH3 / - /, 2.3 / m, 1H, -CH (CH3) - /, 3.8-4.20 (m, 6H, -O (CH2) (3O-), 4.51 (t, J = 5.4Hz, 1H, _- CHO - ^ - J, 5, 15-5.42 (m, 2H, -CH = CH-) 3064 / w / 1640 / w / 1144 / s / 996 / s / 972 / s / pleasant, fresh, medium intense floral with a hint of ambergris

167 975

Publishing Department of the Polish Patent Office. Circulation: 90 copies. Price: PLN 1.50

Claims (1)

Patent claim The method for the preparation of new (E) -3,7-dimethyl-4-octene-1-alu derivatives with the general formula shown in the figure, where n = 2 or 3, characterized in that (E) -3,7-dimethyl-4-octene -1-al is reacted with 1,2-ethandiol or 1,3-propandiol in the presence of catalytic amounts of p-toluenesulfonic acid or pyridine p-toluenesulfonate.