JPS6053030B2 - 4-Alkoxy-1,3-dioxane-5-carbonitrile - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides novel compounds, 4-alkoxy-1,3-
This relates to dioxane-5-carbonitrile.

U,・ Ichifu, 11-Wahba↓ Xane-5-carbonitrile is general formula 〉H-℃H( \(H2-“X (However, in the formula, R represents a lower alkyl group.

). This compound can be easily converted into a raw material for synthesizing vitamins by conventional methods such as hydrolysis reaction, etherification reaction, and alcoholic reaction. For example, 4-alkoxy 1.3-dioxane-5-carbonitrile and alcohol are mixed at a temperature of 40 to 150°C under an acid catalyst such as concentrated sulfuric acid, concentrated hydrochloric acid, hydrogen chloride, P-toluenesulfonic acid, or a solid acid. By carrying out the reaction, 2-dialkoxymethyl-3-alkoxypropanenitrile, 2-alkoxymethylene-3-alkoxypropanenitrile, 2-
Propanenitriles such as methylene-3,3-dialkoxypropanenitrile can be produced.

The 4-alkoxy 1●3-dioxane-5-carbonitrile in the present invention can be produced by reacting 3-alkoxy 2-propenenitrile and formaldehyde in the presence of an acid catalyst. The manufacturing method will be described in detail below.

The 3-alkoxy 2-propenenitrile to be used first has the general formula RO-CH=CH-CN (wherein R represents a lower alkyl group).

). Specific examples include 3-methoxy 2-propenenitrile, 3-ethoxy 2-propenenitrile, 3-n (or i)-propoxy 2-propenenitrile, 3-n (1,.sec or Tert)
-butoxy-2-propenenitrile and the like.
In addition, compounds that form formaldehyde in the reaction system, such as paraformaldehyde, trioxane, tetraoxane, polyoxymethylene, methylal, methylene diacetate, etc., can also be used as formaldehyde.

The amount of formaldehyde used is in terms of aldehyde,
It is preferable to use 1 to 20 mol, preferably 2 to 10 mol, per 1 mol of the 3-alkoxy 2-propenenitrile. Further, specific examples of acid catalysts that can be used include A
lCl3, BF3, BF3・(C2H5)20,. B
F3・(CH3COOH)2, BF3(CH3OH)2
, FeCl3, FeCl2, Zncl2, Sncl2,
Sncl4, CUCl2, CLlCl, TiCl4, T
Lewis acid catalysts such as iCl3; H2SO4, HCl, H
Mineral acid catalysts such as 3PO4; solid acid catalysts such as clay minerals, silica-alumina, silica poria, silica-magnesia, solidified acids, cation exchange resins, sulfates, phosphates, heteropolyacids; etc. can.

In the case of Lewis acids and mineral acids, the amount of these acid catalysts used is 0.001 to 10 mol, preferably 0.01 to 5 mol, per 1 mol of 3-alkoxy 2-propenenitrile.
In the case of solid acids, it is preferably used in moles, and in the case of solid acids, it is used in amounts of 0.
0.01 to 10 parts by weight, preferably 0.05 to 5 parts by weight.

When the amount of acid catalyst used is less than the lower limit, the reaction progresses slowly, while when it is more than the upper limit, the amount of by-products increases. The reaction can be carried out in either liquid phase or gas phase, and can be carried out either batchwise or continuously.

When the reaction is carried out in a liquid phase, it may be carried out without a solvent, but in order to allow the reaction to proceed smoothly, it is preferably carried out in a solvent.

Solvents that can be used include ether solvents such as dioxane, tetrahydrofuran, dimethoxyethane, diethyl ether, diisopropyl ether, and dibutyl ether; benzene, toluene, xylene, hexane, heptane, cyclohexane, cycloheptane, tetralin, decalin, and nitrobenzene. Hydrocarbon solvents such as methylene chloride, chloroform, carbon tetrachloride, 1,2-dichloroethane, etc. Nitrile solvents such as acetonitrile, probionitrile, benzonitrile; acetic acid, propionic acid, methyl acetate , organic acids and their ester solvents such as ethyl acetate and butyl acetate; alcohol solvents such as methanol, ethanol, propanol and butanol; and water. The reaction is carried out at -20 to 300°C, preferably from 0 to 300°C.
It is carried out at a temperature of 25 CfC for 1 to 2 hours under normal pressure or pressurized system.

After the reaction, the target product can be easily isolated and purified by appropriately employing operations such as filtration, extraction, and distillation. Next, production examples of 4-alkoxy 1,3-dioxane-5-carbonitrile in the present invention will be given.

Production Example 1 In a 500ml flask equipped with a thermometer and a calcium chloride tube, 8.31 g of 3-methoxy-2-propenenitrile was added.
y (100 mmol) and 300 y of dioxane (solvent), AICl3l3.3y (
100 mmol) was added.

Next, rose formaldehyde 7.51f (
After adding 250 mmol), 1FI at a temperature of 25°C!
An inter-il reaction was performed. The reaction solution was added to 300 ml of ice water, and then extracted three times with 200 ml of ethyl ether. The extract was washed with saturated brine and dried over sodium sulfate.
Sodium sulfate? After removing the liquid, the liquid was distilled under reduced pressure to determine its boiling point (
5wRHg) 85-87°C colorless transparent liquid 6. I got an anti-L. This compound has an NMR. ．． IR. ．． From the results of MS and elemental analysis, 4-methoxy1●3-dioxane-5
-Identified as carbonitrile. Production Example 2 In the same apparatus as Production Example 1, 12.5V (100 mmol) of 3-n-butoxy-2-propenenitrile and dioxane (
Solvent) 300 fI was charged and stirred at a temperature of 15°C.
BF3・(C2H5)202.13y (15 mmol)
was added.

Next, 7.51f (250 mmol) of paraformaldehyde was added at the same temperature, and then the reaction was carried out at a temperature of 60° C. for 6 hours. The reaction solution was cooled to room temperature, 10.6y (100 mmol) of dry soda carbonate was added, and after stirring at room temperature for 3 hours, the solution was filtered overnight, and the solution was distilled under reduced pressure to a boiling point (5 mHg) of 1
A colorless transparent liquid 11.0f having a temperature of 08 to 110°C was obtained. This compound was analyzed by NMR, . IR. ．． From the results of MS and elemental analysis, it was identified as 4-n-butoxy 1,3-dioxane-5-carbonitrile. Specific examples of the novel 4-alkoxy 1,3-dioxane-5-carbonitrile of the present invention produced according to the above production example are listed in the following table.

Next, an example of the production of propanenitrile, which is known as a raw material for synthesizing vitamin B1, from 4-alkoxy 1,3-dioxane-5-carbonitrile in the present invention will be given as a reference example.

Reference Example: In a 50ml flask equipped with a reflux condenser, 2.58y (25 mmol) of concentrated sulfuric acid was added to 8.0y (8.0y) of methanol.
250 mmol) solution of 4-methoxy 1.
3-dioxane-5-carbonitrile 1.43y (10
mmol) and dioxane (solvent) 16y were charged and the reaction was carried out for 6 hours under reflux and stirring.

As a result, the conversion rate of 4-methoxy1●3-dioxane-5-carbonitrile was 100%, 2-dimethoxymethyl-3-methoxypropanenitrile, 2-methoxymethylene-3-methoxypropanenitrile, 2-methylene-3 ●3-dimethoxypropanenitrile is 6 each
Selectivities of 4.1%, 14.9% and 12.3% were obtained.

Claims (1)

[Claims] 1 4-alkoxy-1,3-dioxane- represented by the general formula ▲ Numerical formulas, chemical formulas, tables, etc. ▼ (wherein R represents a lower alkyl group)
5-Carbonitrile.