SU1046241A1 - Process for preparing monothioacetals - Google Patents

Abstract

METHOD OF OBTAINING. MONOTIO ACETALS about | {Shy formulas where R-H; R2-H, iso-CdH-, based on 1,1-dimethoxyalkane in the presence of a catalyst, characterized in that, in order to increase the yield of the target product, dimethyl diethyl thiosilane is subjected to interaction with a 1,1-dimethoxyalkane at a molar ratio of 1: (O, 5-1.5) at a temperature of (-10) - (+20) s using anhydrous tin tetrachloride as an catalyst in an amount of 0.15-0.6 g per 1 mole of the starting 1,1-dimethoxy alkane. "L

Description

Isolation refers to organic chemistry, specifically to the method for producing mono-acetals of the formula R SCjH. where,, ieo-CjH, which can be used as biologically active compounds, regulating the growth of plants, insecticides and acaricides. Iveve.sten one way of obtaining mono-acetals of formula I by the interaction of 1,1-dimethoxy alkane (in particular 1,1, -dimethoxymethane) with diethylthiomethane at their molar ratio of 1: 1, in the presence of cation exchanger KU-2 in H as a catalyst form, at 40 ° C. 1 J. The yield of the desired 1-label C-1-ethylthiomethane product is always 10%, which is a disadvantage of the improved method. The purpose of the invention is to increase the yield of the target product. This goal is achieved in that according to the method of producing compounds I, which involves the reaction of 1,1-lemexyalkane formulas, in | where R2 have the indicated values with dimethyldiethylthiosilane of the formula CH3 Si YIz (2H5. At their molar ratio l (0.51 , 5), and at (-1-0) - (+20) ° С, in the presence of a catalyst — anhydrous tin tetrachloride, added in an amount of 0.15–0.6 g per 1 mole of dimethoxy alkane. is 94.5 99.3%. Distinctive features of the method are that the interaction with 1,1-dimethoxy alkane is Dimethyldiethylthiosilane at a molar ratio of 1: {0.5-1.5) at (-10) ° - (+20) ° C, using anhydrous tin tetrachloride as an catalyst in an amount of 0.15-0.6 per second 1 of my original 1,1-dimethoxyalkia. Example 1. In a flask equipped with a mechanical stirrer and a thermometer, 118 g (1 mol) of 1,1-dimethoxyisobutane, 180 g (1 mol) of dimethyl diethyl thiosilane, .0.3 g of tin tetrachloride are charged. The temperature of the reaction mixture is maintained at 0 ° C. The process is carried out until the formation of 1-methoxy-1-ethylthioisobutane is stopped. Triethylamine is then added dropwise to the reaction mass to neutralize the medium (pH 7). The mixture is filtered, the filtrate is distilled under vacuum. 147 g (yield 99.3%) of 1-methoxy-1-ethylthioisobutane with a T-144 ° C, 6200.9117, n |, l, 4469 were isolated. Example 2. Analogously to example 1 download 118 g (1 mol) of 1,1 dimethoxyisobutane, 90 g (0.5 mol) of dimethyl diethyl thiosilane. The temperature is maintained, tin tetrachloride is added in an amount of 0.3 g per 1. mol 1,1-dimethoxy isobane. 144 g (yield 97.4%) of methoxy-1-ethylthioisobutane (per starting dimethylethylthiosilane) are obtained. Example 3. In a similar manner to Example 1, 118 g (1 mol) 1,1dimethoxyisobutane, 270 g (1.5 mol) of dimethyldiethylthiosilane are loaded. The temperature is maintained; tin tetrachloride is added in an amount of 0.3 g per 1 mole of 1,1-dimethoxyisobutane. 145 g (98.2%) of 1-methoxy-1-ethylthioisobutane are obtained. Example 4. Analogously to Example 1, 118 g (1 mol) of 1,1-dimethoxyisobutane, 180 g (1 mol) of dimethyl diethyl thiosilane, 0.3 g of tin tetrachloride are loaded. The temperature of the reaction mixture is maintained at 20 ° C. 140 g (yield 94.5%) of 1-methoxy-1-ethylthioisobutane are isolated. Example 5. Analogously to example 1 download 118 g (1 mol) of 1,1 dimethoxyisobutane, 180 g (1 mol) of 1,1-dimethyldiethylthiosilane, 0.3 g of tin tetrachloride. The temperature of the reaction mixture was maintained (. 142.6 g (yield 96%) of 1-methoxy-1-ethylthioisobutane was isolated. Example 6. In a similar manner to Example 1, 76.01 g (1 mol) of 1.1 dimethoxymethane, 180 g (1 mol) was charged dimethyldiethylthiosilane, O, 3 g of tin tetrachloride .The temperature is maintained C. Acquire 104.1 g (yield 98%) of 1-methoxy-1-ethylthiomethane with Tril09c, dO, 9320, ng1.4480. Example 7. Analogously to example 1 load of 76.01 g (1 mol) of 1,1-dimethoxymethane, 180 g (1 mol) of dimethyl diethyl thiosilane, 0.6 g of tin tetrachloride. The temperature of the reaction mixture is maintained O-C. 102.6 g are obtained (yield 96, 5%) H-methoxy-1-ethylthiomethane. Example 8. In the same manner as Example 1, 76.01 g (1 mol) of 1,1-dimethoxymethane, 180 1 (1 mol) of dimethyl diethyl thiosilane, 0.15 g of tin tetrachloride are charged. Temperature of the reaction mixture support 0 ° c.

3, 10.4 2414

103 g (yield 97%) of the 1-label-1,1-dialkoxyalkane are not obtained.

C-1-ethylthiomethane, goal.

Outside of the indicated ratios of reagents 1,1-dimethoxy alkyl, the use of the proposed 1: (0.5-1.5) / owl spodimethyldiethylthiosilane allows to increase the yield of temperature intervals: (- 10) - (+20) C output of mono acetals by 89.3% by

and catalyst 0.15-0.6 g per 1 mol. compared with the prototype.

Claims (1)

METHOD FOR PRODUCING. "'MONOTIOACETALS of the general formula in" and ₅ s> where r'-H; r2-h, iso-C ₃ H ₇ , based on 1,1-dimethoxyalkane in the presence of a catalyst, characterized in that, in order to increase the yield of the target product, dimethyldiethylthiosilane is reacted with 1,1-dimethoxyalkane in a molar ratio of 1 respectively : (0.5-1.5) at a temperature of (-10) - (+ 20) ° C using anhydrous tin tetrachloride as a catalyst in an amount of 0.15-0.6 g per 1 mol of the starting 1,1-dimethoxyalkane · The method of the formula I ^e in which quality