DD281189A5 - PROCESS FOR PREPARING 4,5-DIBENZOYLSELENO-1,3-DISELENOL-2-SELON - Google Patents

Abstract

The invention relates to a process for the preparation of * It is the object to find a synthesis process for the preparation of *, which guarantees good production yields and in contrast to the known electrochemical process is easier to carry out. The task is solved by reacting the * in acetone with benzoyl chloride. * is a suitable starting compound for the preparation of bis-chelates of * (dsis-diselenoisotriselone), which are of interest as components of electrically conducting charge-transfer complexes and as selenium deposits for potential pharmacological use in the treatment of selenium deficiency. {4,5- Dibenzoylseleno-1,3diselenol-2-selon; Bis-chelate; Charge-transfer complex; Selenium deposits; pharmaceuticals; Selenium deficiency; *}

Description

embodiment

Preparation of 4,5-dibenzoylseleno-1,3-diselenol-2-selon

To 0.35 g (0.05 mol) of lithium (in the smallest possible pieces) and 5 g 10, 10 mol) diisopropylamine in 30 ml of dry tetrahydrofuran are added over 2 to 3 hours with vigorous stirring at 40 to 50 ° C internal temperature 2.6g 0.025 mol) Styrene, dissolved in 10ml tetrahydrofuran. The Reaktionsmiseruing is allowed to stand under argon atmosphere at room temperature for 16 hours, then cooled to -6O ⁰ C and treated with 5.5g (0.02 mol) of 1,3-diselenol-2-selon. After one hour, 3g (0.038 mol) red is added to this red-brown solution. After standing at room temperature for 2 hours, the reaction mixture is treated with 6.4 g (0.02 mol) of tetrabutylar. Monombromide dissolved in 100 ml of acetone and with 1.35 g (0.01 mol) of zinc chloride dissolved in a mixture of 10 ml of methanol and 10ml conc. Ammonia solution, reacted. After concentration of the solution in vacuo, the red oily tetrabutylammonium bis (1,3-diselenol-2-selon-4,5-diselenolato) zinkate (li) is dissolved in 150 ml of acetone, filtered and the red-violet filtrate with benzoyl chloride to color change after Yellow biaun titrated. After a short time, orange-red crystals precipitate (4.2 g, 23% of theory). The 4,5-Dibenzoylseleno-i, 3-diselenol-2-selon is recrystallized from chloroform / methanol (mp. 137 to 139 ⁰ C).

Claims (4)

1. A process for the preparation of 4,5-dibenzo seleno-1,3-diselenol-2-selon, characterized in that initially lithium diisopropylamide of lithium, diisopropylamine and styrene in tetrahydrofuran is prepared, which at low temperatures under inert gas (nitrogen or Argon) with 1,3-diselenol-2-selon and then with red selon, after stirring for several hours with tetrabutylammonium bromide dissolved in acetone and ammoniacal zinc chloride solution and then concentrated to an oil which, after being dissolved in acetone, filtered with benzoyl chloride 4,5-Dibenzoylseleno-1,3-diselenol-2-selon is reacted, which is deposited as an orange-red solid and recrystallized from chloroform / methanol. 2. The method according to claim 1, characterized in that lithium diisopropylamide with 1,3-diselenol-2-selon under inert gas atmosphere (nitrogen or argon) at -60 ⁰ C is reacted. 3. The method according to claim 1 and 2, characterized in that is mixed with red selenium at -60 ⁰ C and allowed to react at room temperature for 2 hours. 4. The method according to claim 1-3, characterized in that the formed tetrabutylammonium bis (1,3-diselenol-2-selon-4,5-diselenolato) zincate (II) dissolved in acetone, filtered and the red-violet filtrate with stirring with excess Benzoyl chloride is titrated to yellow-brown until color change to deposit 4,5-dibenzoylseleno-1,3-diselenol-2-selon. Field of application of the invention The invention relates to a process for preparing 4,5-dibenzoylseleno-1,3-diseleno-2-selon, a suitable starting compound for preparing bis-chelates of 1,3-diselenol-2-selen-4,5-diselenolate ( dsis), which are of interest as components for electroconductive charge-transfer complexes and as selenium deposits for potential pharmacological use for the treatment of selenium deficiency symptoms. Characterization of the known technical solutions Already known is the preparation of the 4,6-cisazoylseleno-1,3-diselenol-2-selon by electrochemical reduction of diselenocarbon in dimethylformamide (R.-M Olk, W.Dietzsch, E.Hoyer, Synth. React. Inorg Org. Chem., 14 (7), 915 [1984]). A disadvantage of this SyntesemtuMde is the work with a coarse excess of carbon diselenide, a toxic compound whose elaborate synthesis and processing is associated with strong odor, and the low product yield of this synthesis method. Object of the invention The object of the invention is to provide a chemical synthesis process for preparing 4,5-dibenzylseleno-1,3-diselenol-2-selon, a stable, readily manageable compound useful in the preparation of both organic derivatives and metal Chelates of 1,3-diselenol-2-selon-4,5-diselenolate, which are of interest as components of electroconductive charge-transfer complexes and as selenium deposits for potent pharmacological applications, which guarantees good product yields , as well as being easy to carry out. Explanation of the essence of the invention The object of the invention is to be found in finding a suitable synthesis method for the preparation of 4,5-dibenzoylseleno-1,3-diselenol-2-selon, which can be carried out easily and higher product yields guaranteed than the known electrochemical synthesis method.
According to the invention the problem is solved as follows: First, the preparation of lithium diisopropylamide from lithium and diisopropylamine in an organic solvent such. As diethyl ether, tetrahydrofuran by addition of a styrene-ether mixture at 20 to 50 ° C. Unte; In inert gas atmosphere (N ₂ or Ar) is added to the reaction mixture at low temperatures (-20 to -60 ° with 1,3-disolenol-2-selon.Then is added to this red-brown solution red selenium.After stirring for several hours at room temperature with Tetrabutylammonium bromide dissolved in a ketone such as acetone, methyl ethyl ketone and treated with ammoniacal zinc chloride solution and concentrated in vacuo to an oil.This red tetrabutylammonium bis (1,3-diselenol-2-selen-4,5-diselenolato) zincate , 'll) is dissolved, for example in acetone, filtered and the red-violet filtrate with Öenzoylchlorid with stirring until the color change to yellow-brown titrie.1, wherein the 4,5-Dibenzoylseleno-1,3-diselenol-2-selon, which z , B. can be recrystallized from a chloroform / methanol mixture, separates. The invention will be explained in more detail below using an exemplary embodiment.