CS266107B1 - Enamines of n-methylpyridine iodides and method of their preparation - Google Patents

Abstract

The solution relates to the method of preparing new ones of N-methylpyridinium iodine enamines of Formula I wherein the dimethylaminovinyl group is in position 2, 3 or 4 pyridine ring. Method of preparation of N-methylpyridinium iodine enamines characterized in that N-methylpicolinium iodides of Formula II wherein methyl is in the 2, 3, and 4, respectively. 4 pyridine ring reacts with dimethylformamide dialkyl acetals in an organic solvent environment or in mixtures thereof at 90 ° C to 170 ° C.

Description

wherein the dimethylaminovinyl group is in position 2, 3 resp. 4 of the pyridine ring and a process for their preparation.

The subject compounds have not yet been described in the literature.

The essence of the process for the preparation of enamines of N-methylpyridinium iodides according to the invention consists in that N-methylpicolinium iodides of formula II '' „„ „wherein methyl is in position 2, 3 resp. 4 of the pyridine ring, are reacted with a dimethylformamide dialkyl acetal of formula III / CH _3/2 ND / OR / ₂ (III) wherein R is methyl, ethyl, isopropyl, cyclohexyl, in an organic solvent such as aromatic hydrocarbons such as benzene, toluene, xylene, the ethers such as dibutyl ethers, tetrahydrofuran, dioxane, further in dimethylformamide, dimethylacetamide or mixtures thereof at a temperature of 90 ° C to 170 ° C.

Reaction. proceeds according to the reaction scheme:

h ₃ c-nO — ch ₃ 4- (ch ₃ ) ₂ nch (or | _{2 -} 5 * h ₃ ci \ ((J ^ —ch = ch-n (ch ₃ | ₂

I® _{| Θ}

According to the process of the invention, highly reactive enamines are prepared with a wide range of uses (Cook G. A .: Enamines: Synthesis, Structure and Reactions, Marcel Dekker, New York 1969). The subject compounds can serve as starting products for the preparation of new heterocyclic compounds, natural substances, as well as polymer additives.

The following examples illustrate but do not limit the scope of the invention:

Example 1

22.1 g of 1,2-dimethylpyridinium iodide in 20 ml of dimethylformamide dimethyl acetal were heated for 10 h in 50 ml of dimethylformamide at 140-150 ° C. After distilling off the solvent in vacuo, the residue was crystallized from methanol-ether. 20 g of 2- [N, N-dimethylaminovinyl] -1-methylpyridinium iodide of m.p. t. 196-198 ° C (dec.).

1 H-NMR spectrum in hexadeuterodimethylsulfoxide delta (ppm): 3.00 (s, 3H), 3.23 (H, 3H) -N (CH ₃ ) ₂ ; 3.84 (s, 3H) 8.21 (d, 1 H), 5.09 (d, 1 H) J = 12.5 Hz; 8.25, 6.88-8.00 (m, 4H)

Example 2

22.1 g of 1,3-dimethylpyridinium iodide in 20 ml of dimethylformamide dicyclohexyl acetal and ml of xylene and 20 ml of dibutyl ether were heated in an autoclave at 170 DEG C. for 24 hours. After distilling off the solvent, 10 g of 3- (N, N-dimethylaminovinyl) -1-methylpyridinium iodide salt of m.p. t.

CS 266 107 Bl

198-207 ° C (dec.).

1 H-NMR spectrum in hexadeuterodimethylsulfoxide delta (ppm): 2.89 (s, 6H) -N (CH ₃ >₂; 4.19 (s, 3H) 7.59 (d, 1H), 5.05 (d , 1H), J = 12.5 Hz, aromatic H 8.71 (d, 1H), 8.00-8.4 (m, 2H), 7.69 (dd, 1H)

Example 3

22.1 g of 1,4-dimethylpyridinium iodide in 20 ml of dimethylformamide and 20 ml of dioxane were heated with 20 ml of dimethylformamide diisopropyl acetal at 160-170 ° C in an autoclave. After heating for 10 h, the solvent was distilled off in vacuo and the residue was purified by crystallization from methanol-ether. 4- (N, N-dimethylaminovinyl) -1-methylpyridinium iodide was obtained in 71% yield as a substance with m.p. t. 146-154 ° C (dec.).

1 H-NMR spectrum in hexadeuterodimethylsulfoxide delta (ppm): 2.48 (s, 3H), 2.93 (s, 3H) -N (CH ₃ ) ₂ ; 3.84 (s, 3H) 2 -CH ₃ ; 8.04 (d, 1 H), 5.25 (d, 1 H), J = 12.8 Hz; 8.03 (d, 2 H), 7.3 (d, 2 H).

Claims (2)

Enamines of N-methylpyridinium iodides of the formula I ch = ch-n (ch ₃ ) ₂ · 1 ° (I) wherein the dimethylaminovinyl group is in position 2, 3 or 4 of the pyridine nucleus. 2. The means by the preparation of N-methyl pyridinium -propanamine iodides of formula I according to claim 1 characterized in that the N-metylpikolíniové iodide of formula II (II) wherein is methyl in the 2, 3 or 4 of the pyridine nucleus are reacted with a dimethylformamide dialkyl acetal of formula III / CH _3/2 nch / or / ₂ (III) wherein R is methyl, ethyl, i-propyl, cyclohexyl in the environment of organic solvents such as aromatic hydrocarbons such as benzene, toluene, xylene, ethers such as dibutyl ethers, tetrahydrofuran, dioxane, further in dimethylformamide, dimethylacetamide or in mixtures thereof at a temperature of 90 ° C to 170 ° C.