DD224590A1 - PROCESS FOR THE PREPARATION OF 6-ARYL-2,4-BIS (DIALKYLAMINO) -1,3,5-OXADIAZINIUM SALTS - Google Patents

Abstract

Process for the preparation of 6-aryl-2,4-bis (dialkylamino) -1,3,5-oxadiazinium salts. It is the object of the invention to develop a simple and economical synthesis route for the preparation of 6-aryl-2,4-bis (dialkylamino) -1,3,5-oxadiazinium salts of general formula 1. According to the invention, dialkylcyanamide and aromatic carboxylic acid chlorides are reacted in the presence of a LEWIS acid, preferably tin tetrachloride, antimony pentachloride or aluminum chloride, in a molar ratio of 2: 1: 1. The pentachlorostannates are characterized with perchloric acid or sodium perchlorate as 6-aryl-2,4-bis (dialkylamino) -1,3,5-oxadiazinium perchlorates of general formula 1. The compounds produced in this way can be used as an excellent starting point for a number of new organic syntheses, in particular of bioactive substances.

Description

Process for the preparation of 6-aryl-2,4-bis (dialkylamino) -1,3 * 5-oxadiazinium salts

Field of application of the invention

The invention relates to the preparation of 6-aryl-2,4-bis (dialkylamino) -i, 3,5-o.xadiaziniumsalzen the general formula 1, wherein R = alkyl, Alkyloicy-, halogen or nitro

groups, R and R · ^ are alkyl groups and R and R · are a ring with η methylene groups, with η = 4 or 5 "or a ring of four methylene groups and one oxygen atom, which is preferably arranged between in each case two methylene groups. Z is ClO ^, SbCIg or 1/2 SnCl.

The "compounds of the general formula I _- can be used as an excellent starting point for a number of new organic syntheses, in particular of bioactive substances.

Characteristic of the known technical solutions

6-aryl-2,4-bis (dialkylamino) -1,3j5-O-xadiazinium salts of the general formula Λ. have been synthesized in two different ways.

'Bredereck K. and R. RICHTER (Ber. Chem. 22 (1966) 2454) describe the reaction of dialkylcyanamide with benzoyl chloride at 150 ⁰ C. With this method, they could only the 2,4-bis (dimethylamino) -6- Isolate phenyl-1,3,5-oxadiazinium perchlorate in low yield (16%). Compounds of this type with a different substituent pattern were not available.

H. HAKDMAJM, J. LIEBSCHER and P. CZERHEY (DD-PS-138206 17.10.19979) prepared the 6-aryl-2,4-bis (dialkylamino) -1j3 _J 5-oxadiazinium salts from 1-aroyl-3 » 3- <aialkyl-thioureas and inorganic acid chlorides such as thionyl chloride or phosphorus pentachloride forth. Two molecules of the corresponding thioureas react with the loss of sulfur and an aroyl residue. Apart from these by-products and the use of the auxiliary reagents thionyl or phosphorus pentachloride, the overall three-step synthesis adversely affects the economics of the reaction.

Aim of the invention;

The aim of the invention is to develop a simple and economical synthetic route for the preparation of 6-aryl-2,4-bis (dialkylamino) -1,3> 5-oxadiazinium salts.

Explanation of the essence of the invention

The object of the invention is to implement dialkylcyanamides of general formula 2 and aromatic carboxylic acid chlorides of general formula J3 in the presence of a LEWIS acid, such as tin tetrachloride, antimony pentachloride or aluminum chloride. According to the invention, the abovementioned reactants are reacted in a molar ratio of 2: 1: 1 in an inert solvent and the 6-aryl-2,4-bis (dialkylamino) -1,3> 5-oxadiazinium salts of the general formula I _- in good to very good Obtained yields. In addition to achieving high product yields, a variety of substituent variations are possible in this reaction. Due to the additive composition of the reaction product from the reactants in angegeeben molar ratio no by-products are obtained. The dialkylcyanamide and the aromatic carboxylic acid chloride are mixed in a solvent, preferably chloroform or dichloromethane, at low temperatures with the LEWIS acid. The reaction is then continued at room temperature with stirring and stopped after twelve hours. The

Reaction products, preferably the Pentachlorostannate be transferred for better characterization with perchloric acid or sodium perchlorate in the perchlorates. The dialkylcyanamides of general formula 2 can easily be prepared by processes known per se. The aromatic carboxylic acid chlorides of the general formula J are accessible by reaction of the corresponding carboxylic acids with thionyl or phosphorus trichloride in a manner known per se.

embodiments

The invention will be explained in more detail below with reference to three examples:

Dialkylcyanamide 0.05 mol and 0.025 mol of aromatic carboxylic acid chloride are dissolved in 50 dl dry chloroform and cooled to temperatures of about 0 ⁰ C. 0.025 mol of tin tetrachloride in 10 ml of dry chloroform are added dropwise to this solution while cooling. At room temperature, it is then stirred for another 12 hours

 Unusual products are sucked off; otherwise the solvent is evaporated in vacuo. The crystalline or oily product is taken up in 40 ml of dry alcohol and mixed with 4 g of 70 percent perchloric acid or the appropriate amount of sodium perchlorate. Upon addition of ether and deep cooling, the perchlorates precipitate in crystalline form. These are then recrystallized from the specified solvents. Further details in the listed table.

Beispiel_2j_

0.05 mol of pentamethylene cyanamide and 0.025 mol of benzoyl chloride are dissolved in 50 ml of dry dichloromethane. At temperatures below 0 ⁰ C, 0.025 mol of antimony pentachloride are added dropwise to this solution. After stirring for 12 hours at room temperature, the pale yellow product is filtered off with suction and recrystallized from glacial acetic acid (compound 1o ).

0.05 mole of pentamethylene cyanamide and 0.025 mole of p-nitrobenzoyl chloride are dissolved in 50 ml of dry toluene. 0.025 mol of tin tetrachloride are added dropwise to this solution. The mixture is then refluxed for four hours, whereby a red-brown oil separates. This is separated and dissolved in a little dry acetonitrile. After a short time yellowish crystals begin to precipitate. These are filtered off and recrystallized from a little dry acetonitrile (compound 1n).

table

Compounds obtained of the general formula J _-

R-

Schmp, ο ,.

Yield,

H H Ξ H H

ClO

- (CH ₂ ) ₄ -

, ClO,

ClO

ClO

- (CHg) ₂ -O- (CH _{2) 2} - ClO ₄

"™ 0x1 ο L / -pXi ξ- O ^ XX er

- (0Η ₂ ) ₅ -

CiO

ClO

- (CH ₂ ) ₂ -O- (CH ₂ ) ₂ - GlO ₄

4-CHOO C ₂ H. C ₂ H.

4-CH ₃ O - (CH ₂ ) ₅ -

k 4-Cl

4-Cl

m 2 Cl

η 4-ΝΟ,

ο Η

(CH ₂ ) ₅ - (CH ₂ ) ₄ - (CH ₂ ) ₅ -

ClO ₄ ClO ₄ ClO ₄

CiO ₄

ClO ₄

1/2 SnCl ₆ SbCl 78

84

86

91

280-281

(Methanol) -179-181

(Glacial acetic acid) 234-236

(Methanol) 208-210

(Acetonitrile) 255-257 90 (glacial acetic acid) 167-170

(Ethanol)

235-237

(Methanol) 275-278

(Glacial acetic acid) 166-168

(Ethanol)

223-225

(Methanol)

82

78

88

58

70

70

(Glacial acetic acid) 229-232 64 (glacial acetic acid) 174_176 77 (methanol) 213-215 32 (acetonitrile) 214-216 67 (glacial acetic acid)

Claims (4)

- 6 claims 1. A process for the preparation of 6-aryl-2,4-bis (dialkylamino) -1,3) 5-oxadiazinium salts of the general formula 1_ characterized in that a dialkylcyanamide of the general formula 2, an aromatic carboxylic acid chloride of the general formula J3 in the presence a LEWIS acid, in particular tin tetrachloride or antimony pentachloride, be reacted, wherein the radicals R are the same alkyl, 2 3 alkyloxy, halogen and nitro groups, R and- Έτ 2 3 and R and R ^ are a ring with η methylene groups, where η is four or five, and a ring with four methylene groups and one oxygen atom, which is preferably arranged between each two methylene groups, and X is Cl (X, SbCIg or 1/2 SnCIg. 2. The method according to claim 1, characterized in that the dialkylcyanamide, the aromatic carboxylic acid chloride and the LEWIS acid in a ratio of 2: 1: 1 are used. 3. Process according to claims 1 and 2, characterized in that the resulting 6-aryl-2,4-bis (dialkylamino) -1 »3,5-oxadiazinium salts of the general formula _1 are converted with perchloric acid or sodium perchlorate in the perchlorates. 4. Process according to claims 1 to 3, characterized in that halogenated hydrocarbons and alcohols are used as the solvent. For this purpose! Page formulas