CS254207B1 - 3- (5-Hydroxy-2-furyl) -3-cyano-2-substituted propenoic acid derivatives and their preparation - Google Patents

Abstract

The solution concerns new 3-(5-halo-2-furyl)-3-cyano-2-substituted propenoic acid derivatives. The essence of the method of preparation is that 3-(5-halo-2-furyl)-2-substituted propenoic acid derivatives are treated with alkaline cyanide in a dimethylformamide-water environment, and after acidification with acetic acid, the reaction mixture is treated with lead acetate in a temperature range of -10 to -30°C.

Description

254207 «τ Q»

The present invention relates to 3- (5-halo-2-furyl) -3-cyano-2-substituted acid propylene derivatives of formula (Ia) .J-c-CnCNJ-y cm-1 (Y is CN, COOCH 3, GOOC 2 H 5 or COClH6 - CH3 - (p) and X is chlorine, bromine or iodine and the preparation of similar compounds of furan includes the preparation of 2-tricyanovinylfuran by condensation of malondinitrile with furoyl cyanide in a low yield (U.S. Pat. No. 2,813,116; Chem., Abstr., 52, 4777a (1958); J. Amer. Chem. Soc. 80, 2815 (1958)], 5-methyl-2-triyanovinylfluane by reaction of 2-methylfuran with tetracyanoethylene (J. Amer Chem., Soc., 83, 1652 (1961), and 5-triyanovinyl-2-furaldehyde hydrazones, respectively, obtained from the respective 2-furaldehyde hydrazones by treatment with tetrakynoethylene (U.S. Pat. No. 3,058,977; 58. 14 164 B (1963); J. Amer. Chem. Soc. 83, 1652 (1961).

The principle of the preparation of the compounds according to the invention is that the 3- (5-halo-2-furyl) -2-substituted acrylonitrile of the general formula II

wherein X and Y are as defined above, are treated with alkali cyanide, preferably sodium cyanide in dimethylformamide. Water and, after acidification with acetic acid, the reaction mixture is treated with lead acetate in the range of -10 DEG to 30 DEG C. The advantage of this process is that it is based on the raw materials available (D. Ilavsky, Habitat, Bratislava 1982) and the reaction is transferred in a single vessel, in good yield, without isolation of the intermediate.

The synthesized compounds represent a novel group of reactive 5-substituted 2-halofuranes with a wide range of further applications for the preparation of biologically active preparations, synthetic intermediates of furyl-substituted heterocycles, synthetic dyes and the like. At the same time, the compounds prepared are suitable models for elucidating the theoretical aspects of the electrophilic heteroarylation of aromatic derivatives.

The subject matter of the invention is illustrated by way of example 4 without departing from the exclusive scope thereof. Example 1 2-Bromo-5- (triyanovinyl) furan

To a solution of 5-bromofurfurylideneandinitrile (4.46 g; 0.02 mole) in dimethylformamide (25 mL) cooled to Q10 ° C, the sodium cyanide solution (1.0 g; 0.0204 mole) was added. ) in water (2 mL), then acetic acid (50 mL) is added and over 5 min. add lead lead Pb (OCO-CH 3) 4 (9.0 g; 0.0203 mole) in small portions. The reaction mixture was stirred for 30 minutes, poured into 400 ml of ice water, filtered and crystallized from water. toluene-heptane 1: 1 to give 3.2 g (65%) of pure product. Mp = 160-162 ° C.

For C9H2BrN3O: calculated: 43.6% C, 0.81% H, 16.94% N, 32.2% Br, found: 43.71% C, 0.83% H, 16.82% N, 32 Example 2 2-Iodo-5- (triyanovinyl) furan

A solution of sodium cyanide (0.5 g; 0.0102 mol) in water (2 ml) was added to a solution of 5-iodofurfurylideneaminedinitrile (2.7 g; 0.01 mole) in dimethylformamide (15 ml) cooled to 0 ° C with stirring. ), acetic acid (40 ml) was added and lead dioxide (5 g; 0.011 mol) was added in small portions. Further work-up as in Example 1. Yield 2 g (68%) of product. Mp = 182-185 ° C (toluene-heptane 1: 1).

For C9H2IN3O: calculated: 36.64% C, 0.68% H, 14.24%, found 36.75% C, 0.72% H, 14.32% N. Example 3 2-Chlorine -5- (triyanovinyl) furan

A solution of sodium cyanide (0.5; 0.0102 mol) in water was added to a solution of 5-chlorofurfurylidenedionitrile (2.04 g; 0.01 mole) in dimethylformamide (15 mL) cooled to 0 ° C. 2 ml), add acetic acid (40 ml) and in small portions

Claims (3)

234207 eggs are added lead (5 g; 0.011 mol). Further work-up as in Example 1. Product yield 52%. Mp = 130-132 ° C (toluene-heptane 1: 4). For C9H2ClN3O: calculated: 53.10% C, 0.99% H, 20.64% N, 17.41% Cl; Found: C, 53.25; H, 1.08; N, 20.51; Cl, 17.53. Example 4 3- (5-Bromo-2-furyl) -2,3-dicyanopropenoate methyl To a solution of 3- (5-bromo-2-furyl) -2-cyano-propenoate methyl (2.8 g; 0; Sodium cyanide (0.5 g; 0.0102 mol) in water (1.5 mL) was added at 0-10C under stirring. Add acetic acid (40 mL) and add acetic acid (5 g; 0.011 mol). After working up as above, the crude product is passed through a silica gel column (toluene eluent). After evaporation of the solvent, 2.1 g (75%) of the product are obtained as a 1: 1 mixture of (E) -α (Z) -isomers (determined from 1 H NMR spectra, Tesla BS 487/80 MHz). (Z) -isomer (?, Ppm): 6.99 (d, 1H, H3), 7.83 (d, 1H, H4), J34 = 3.95 Hz, 3.97 (s, 3H, CH3) . (E) -isomer (5 ppm): 7.05 (d, 1H, H3), PREDMET 1.3- (5-Halo-2-furyl) -3-cyano-2-substituted propenoic acid derivatives wherein Y is CN, COOCH 3, COOC 2 H 5 or COC 5 H 4 -CH 3 -P) and X is chloro, bromo or iodo. 2. Method for the Preparation of Compounds of General 7.65 (d, 1H, H4), J34 = 3.95 Hz, 3.96 (s, 3H, CH3). Spectra measured in hexadeuteroacetone. For C10H5BrN2O3: calculated: 42.73% C, 1.79% H, 28.43% Br, 9.97% N; Found: 42.90% C, 1.95% H, 28.10% Br, 9.52% N. Example 5 3- (5-Bromo-2-furyl) -3-cyano-2-nitrile ( 4-Toluoyl) propenoic acid To a solution of 2- (4-toluoyl) -3- (5-bromo-2-furyl) propenoic acid nitrile (1 g; 0.0032 mol) in dimethylformamide (10 ml) is added sodium cyanide solution (0%). , 25 g; 0.0051 mol) in H 2 O (1 mL) and stirred for 10 min. Acetic acid (20 ml) was added and lead (II) acetate (2 g; 0.0045 mol) was added in small portions. and poured into 200 ml of ice-water. The product is filtered off with suction and crystallized from the carbon tetrachloride-heptane mixture. 0.5 g (46%) of the product is obtained. Mp = 154-156 ° C. For C16H9BrN2O2: calculated: 56.33% C, 2.66% H, 23.42% Br, 8.21% N; Found: C, 56.58; H, 2.85; Br, 23.61; N, 8.04%. Formula I, characterized in that 3- (5-halo-2-furyl) -2 -substituted acrylonitrile of general formula II, * CH 2 C (CN) -Y (fll where Y and X are as defined above, is treated with alkali cyanide, preferably sodium cyanide, in dimethylformamide-water and after acidification with acetic acid to the reaction) the mixture is treated with lead acetate in a temperature range of -10 to -30 ° C.