HU189391B - Process for preparing 9,10-bis/phenyl-ethinyl/-anthracen derivatives - Google Patents

Abstract

9,10-Bis-(phenyl -ethynyl)-anthracene derivs. of formula (I) are prepd. by reacting an anthraquinone deriv. of general formula (II) with 4 equivs. of a Grignard reagent of general formula (II) in an ether solvent or an ether-benzene or ether-toluene mixt. at 20-60 deg.C for 2-4 hours, acidifying the reaction mixt. to pH 2-3 and stirring it subsequently at 0-5 deg.C for 1-3 hours. The pptd. prod. is sepd. by filtration and washed with acetic-acid. - In the formulae R = 1-4C alkyl gp., or halogen, pref. Cl, X is chlorine, bromine or iodine.

Description

The present invention relates to a process for the preparation of 9,10-bis (phenylethynyl) -anthracene derivatives of formula (I) by reacting anthraquinone derivative (H) with four times the stoichiometric amount of the Grignard compound of formula (III).

We use the following notations in our application:

- R is a hydrogen atom; C 1 -C 4 -alkyl; such as methyl, ethyl, η-propyl, isopropyl, η-butyl, sec-butyl, isobutyl, tert-butyl; and halogen, preferably chlorine.

X is chlorine, bromine or iodine.

The meaning of the substituents R and X is not altered in this specification and therefore is not repeated.

The compounds of formula (I) are used as components of fluorescent and chemiluminescent compositions. a 3 704 231, 3 729 4 26, 3 74 9 6 79, 3 775 336. App. No. 3,888,786. U.S. Patent Patents.

For the preparation of the compounds of formula I, the literature discloses the following routes:

a) G. Rio (Compt ', re _n d.227.937-9 / 1948 //) (CA 43 3401 d) reacts anthraquinone with bromo-magnesium-phenyl-acetylide and the 9,10-bis (phenylethynyl) thus obtained. -9,10-Dilyldroanthracene-9 ₎ 10-Doil with iodine hydrochloric acid or potassium iodide sodium hypophosphite in acetic acid gives the target compound (R41) in a yield of 10-20%. Reduction with metallic zinc, metallic magnesium or titanium trichloride in a methanolic medium as described above gives similarly low yields of 9,10-bis (phenylethyl) anthracene (Ann. Chinin / Paris / 1954.9,182).

b) W.Ried et al. (Chem.Ber.94.1046-50 (1961)), by reacting lithium phenylacetylide with anthrathonone, to prepare 9,10-bis (ferritinyl) -9,10-dihydroanthracene-9,10. diol from which 9,10-bis (phenylethynyl) -anthracene is obtained in less than 50% yield by reduction with tin (II) chloride in acetic acid.

c) U.S. Patent Nos. 3,729,426 and 3,557,233. U.S. Patent Nos. 4,309 and 6,101, which form lithium amide from ethylbenzene to form lithium phenylacetylide and then react with anthraquinone in dioxane medium. The resulting 9,10-bis (phenylethynyl) -9,10-dihydroanthracene-9,10-diol is isolated after reduction with tin (II) chloride in acetic acid and aqueous acetic acid, respectively. In both cases, it is reported that 9,10-bis (phenylethyl) anthracene can be prepared in less than 50% yield (based on anthraquinone).

d) An improved version of the above described methods of preparation is disclosed in U.S. Patent No. 3,911,038. U.S. Pat. No. 4,123,123, according to which 9,10-bis (phenylethynyl) -9,10-dihydroanthracene-9,10-diol, analogous to the above method, in a mixture of dioxane and dimethylformamide, without isolation, in tin (II} is directly reduced to 9,10-bis (phenylethynyl) anthracene by chloride to give the target compound in a 68% yield.

The above-described methods of preparation of 9,10-cis (phenylethynyl) -anthracene described by G. Rio and W. Ried et al., And U.S. Pat. A common disadvantage of the methods known in the US patents is that they produce the target compound in only 50% cumulative production. No. 3,911,038. The US application already provides the target compound in good (about 70%) yield, but the disadvantage of this method of preparation is that the lithium phenylacetyl and render reaction reaction · capable of producing ethynyl benzene with lithium anhydride.

(Lithium anhydride can be prepared in anhydrous ammonium metal lithium ball in liquid ammonia; in special apparatuses, under special conditions at -78 ° C, under an argon or nitrogen atmosphere.)

The present invention is based on the surprising discovery that the anthraclnone derivative (II) is reacted with a 4-fold stoichiometric amount of the Gragnard chemical (III) in one step to form the 9,10-bis (phenylethynyl) -anthracene derivative (I) . The process according to our application provides the target glassylet with good yield (about 70%). Expensive and highly reactive lithium anhydride is not used in the preparation.

The process is prepared from four equivalents of C 1-4 alkyl halide and magnesium ball in ether solvent or ether (benzene or ether) in toluene and four equivalents of ethinylbenzene are added after complete dissolution of the magnesium. After removal of the corresponding C 1 -C 4 alkane, one equivalent of anthrathonone derivative is added to the mixture and the components are reacted for 2 to 4 hours at 20 ° C to 60 ° C. The product can be isolated by filtration after acidification (pri = 2), stirring for another 13 hours, and heating.

Our procedure is. The following examples are set forth in greater detail, but are not limited to these examples:

Example 1 _:

Ethyl bromide (9 mL, 0.12 M) was added dropwise to 245 g (0.1 M) of magnesium in 100 mL of absolute tetrahydrofuran. To the Grignard reagent thus obtained, 12 ml (0.11 M) of ethinylbenzene was added dropwise at 40 ° C. After gas evolution ceased, 5 g (0.024 M) of anthraquinone was added and the temperature was maintained at 50-55 ° C for two hours. The reaction mixture was adjusted to pH 2 with 10% hydrochloric acid, cooled to 0 ° C, stirred for one hour, and the precipitated crystals were filtered.

The mother liquor was treated with 100 ml of 96% acetic acid, filtered again, washed with acetic acid and combined. 6.4 g (70%) of 9,10-bis (ferriethynyl) anthracene are obtained. The product was recrystallized from benzene. mp 250-251 ° C.

Example 2;

Ethyl bromide (9 mL, 0.12 M) was added dropwise to 2.45 g of magnesium (0.1 M) in 100 mL of absolute tetrahydrofuran. To the resulting Grignard reagent was added 12 ml (0.11 M) of ethinylbenzene at 35-40 ° C. After the evolution of gas had ceased, 5 g (0.025 Mu) of 1-chloro-anthrathonone was added, the temperature of which was adjusted to 45-50 ° C, and the reaction mixture was stirred at this temperature for 2 hours. hydrochloric acid (pH = 2), the reaction mixture is cooled to 0 DEG C., stirred at this temperature for three hours, and the precipitated crystals are filtered off and washed with acetic acid.

189 391

The product was 7.1 g (69%) of 6-chloro, 9.10-bis (phenylethynyl) -anthracene, recrystallized from benzene, m.p.

Example 3;

Grignard reagent was prepared from 2.45 g (0.1 M) magnesium in 9 ml (0.12 M) ethyl bromide in 100 ml absolute tetrahydrofuran and 12 ml (0.11 M) ethinyl benzene was added dropwise at 40 ° C. and the reaction mixture is stirred at this temperature until gas evolution ceases. It is then added dropwise to a suspension of the obtained 2.9 g (0.025 M) 2-ethyl anthraquinone and 50 ml of absolute benzene at 20-25 ° C. After addition, the reaction mixture is stirred for 2 hours at 45-50 ° C and then adjusted to pH 2 with 10% hydrochloric acid.

After acidification, the material was cooled to O'C, and after stirring for two hours, the crystals were filtered and washed with acetic acid. The product was 4.1 (40%) 2-ethyl, 9,10-bis (phenylethynyl anthracene) which was recrystallized from benzene, m.p. 230-2 ° C.

Claims (2)

A process for the preparation of 9,1-bis (phenylethynyl) -anthracene derivatives wherein R is hydrogen in the formula (I). or a halogen atom, preferably a chlorine atom, characterized in that it is an anthraquinone. - a derivative wherein R is reacted with four equivalents of the above compound Grignard of formula II - X is chlorine, bromine or iodine - in ether solvent or ether benzene, ether 111 in toluene solvent 20 The reaction mixture is acidified to pH 2-3, then stirred at 0-5 for 1-3 hours, and the precipitated product is isolated by filtration and washed with acetic acid. 2. The process of claim 1 wherein the ether solvent is tetrahydrofuran.