SU396330A1 - WAY OF OBTAINING p-ALKINYL SUBSTITUTED FURANS - Google Patents

Description

The invention relates to a new way of combining new compounds - | 3-alkynyl-substituted furans of the formula I, where R and RI are alkyls, which can serve as intermediates in the organic syndrome. The proposed method consists in the fact that the primary-tertiary patterns of the acetylene series of the formula AND CHC-I, -CH-z where R and RI have the above values, are subjected to intramolecular cyclization by heating in the presence of a catalyst and the desired product is isolated by conventional techniques. The cyclization is carried out in a solution or a melt, and copper chloride is used as a catalyst. Example 1. Preparation of 2-methyl-4- (1-l-o-vinyl) - furan. 10 g of 4-methyl-2- (1-propiyl) -3-but1 1H-1,2-diol is heated for 30 minutes at 90-100 ° C with a catalytic amount of CuCl in a sealed ampoule. The product is extracted with ether, dried, the ether is distilled off, the residue is distilled in a vacuum. Get 7 g of furan. Output 80%. T. Kip. 7ГС / 20 l (l, n2 ° 1.5060, df 0.9695; .MR found 36.82; MR calculated 35.88. Found, C 79.69; 79.82; H 6.83, 6.98 ; Csl-hO. Calculated,%: C 79.97; H 6.71. To characterize the resulting furan, remove IR and NMR spectra. In the PC spectrum, the main absorption bands of the furan ring were detected (810, 920, 1050, 1138 , 1550, 1615, 3125 cm), the absorption band of disintegrated acetylene bond is 2255 si. In the NMR spectrum there are sigals (b, ppm): 1.90 (ZP, Furan-substituent), 2.15 ( ZN, CH3 with acetylene bond), 5.90 (1P, (Z-proton), 7.35 {1H a-proton). Example 2. Preparation of € 2 g “L-4- (1-olpropyl) -fura11a. 9-10 g of 4-methyl-2- (1-proppnyl) -3-butin-1,2-di la is dissolved in 50 ml of benzene and heated with a catalytic amount of CuCl to reflux for 1 hr. Yield 76%.

The results of the elementary analysis, as well as the IR and NMR spectra of the obtained product are similar to Example 1.

Example 3. Preparation of 2-butyl-4- (1-hexynyl) furan.

5 g of 2- (1-hekenyl) -3-octy-11-1,2-diol are heated in a pre-precipitated amoule with a catalytic amount of CuCl at 100-110 ° C for 1 hour. 3.8 g of the corresponding furan was recovered, yield 82%, i.e. kin. 66-67 C / 2 mm, pi 1.5025.

Found,%: C 82.20; H 9.75. Sinzo

Calcined,%: C 82.33; P 9,83. In the 2-butnl-4- (1-hexynyl) furan PC-spectrum, the following lotting bands are present: 817, 925, 1045, 1140, 1550, 1620, 3120 cm — main bands: absorption of the furan ring, 2250 cw — substituted acetylene bond .

Subject and reference

Receiving procedure

(3-alkynyl-substituted furans of formula

With sEEC, -Ri

ABOUT

R

where R n RI is alkyl, characterized in that the primary tertiary iso-glycols of the acetylene series are subjected to intramolecular cyclization by heating in the presence of a catalyst and the target product is isolated by ordinary

tricks.

2. A process according to claim 1, characterized in that the cyclization is carried out in solution or melt.

3. Method according to paragraphs. 1 and 2, distinguished by 11 {ice in that the cyclization was carried out in

the floor of hl shr Peto and M edN.