DD214377A1 - PROCESS FOR THE SYNTHESIS OF 3-SUBSTITUTED 1-THIOACYLTHIUM SUBSTANCES - Google Patents

Abstract

The invention relates to a process for the synthesis of 3-substituted 1-thioacylthioureas and their metal complexes. The stated object is achieved according to the invention that 1,2,4-dithiazole-3-thiones are cleaved by primary or secondary amines and triorganophosphines or phosphites, wherein the substituted thioacylthioureas formed are to be separated by treatment with lye v.other reaction products , The compounds obtained can be used in crop protection and for metal extraction.

Description

Process for the synthesis of 3-substituted 1-thioacylthioureas Field of application of the invention

The present invention opens a new route to the synthesis of urea type oxo compounds of interest for plant protection and metal extraction applications

Characteristic of the known technical solutions

3-Substituted 1-thioacylthioureas are accessible by reaction of thioamides with alkyl and aryl isothiocyanates in a strongly basic medium {H. Hartmann, E. Ulemann, W. Huebner, E. Ludwig, LBeyer, M.Walter, E.Hoyer: Z. Chem.21 [1981, 271]. 3,3-Disubstituted 1-thioacylthioureas are obtained in some cases by thioacylation of thioureas mitfhiobenzoylthiogiykolsäure (E.Uhlemann, W.Hübner, E.Ludwig: Z. Chem21 [1981] 413) or by reaction of N (N ' , N'-dialkylaminothiocarbonyD-benzimidchloriden with sodium sulfide {L.Beyer, R.Widera, E. Hoyer: Z. Chem.21 [1981] 415). The reactions mentioned are narrowed in their scope by the availability and stability of the required isothiocyanates and often require several intermediates, so that there is a need for a simple, universally applicable procedure. -J / '' · '·.''. M ^ - ^ ''^;

Aim of the invention _;

The goal of the invention is to make 3-substituted 1-thioacylthioureas having a wide variety of substituents accessible by a simple process.

Explanation of the essence of the invention

The invention has for its object to provide a pathway that allows the synthesis of 3-substituted 1-thioacylthioureas in good yield and can be used in terms of production. It has been found that thioacylthioureas of the formula I

R ¹ -CS-NH-CS-NC (I)

^ 3;

where R ^{1 is} alkyl, aryl or hetaryl,

R ² , R ^{3 are} hydrogen, alkyl, aryl, hetaryl, which may also be optionally mono- or polysubstituted by alkyl, alkoxy, halogen, nitro or cyano groups, may be substituted

R ² and R ³ together with the connecting nitrogen atom and optionally with a further heteroatom (O, S, N)

form a 5- or 6-ring.

and their complexes with transition metals such as nickel and cobalt by cleavage of 1,2,4-dithiazole-3-thiones with equimolar amounts of primary and secondary alkyl, aryl and hetarylamines and triorganophosphines or phosphites such as triphenylphosphine or triethyl phosphite in inert solvents Temperatures of -30 to +50 ⁰ C are formed with good yields. Suitable solvents are in particular dichloromethane or tetrahydrofuran. After evaporation of the solvent, the present thioacylthioureas are separated from the organophosphorus sulfides by treatment with brine and precipitated with acid under cooling. With addition of metal salts such. For example, nickel and cobalt alkanates to the reaction solution, the corresponding metal complexes are obtained, to free by digestion with organic solvents of accompanying organophosphorus sulfides

The 1,2,4-dithiazole-3-thiones required as starting materials are readily available from acyl isothiocyanates and phosphorus (V) sulfide. (J.W. MacDonald, D. M. McCinnon: Canad. J. Chem. 45 [1967] 1225). It is particularly advantageous in the process according to the invention that the use of difficultly accessible or less stable isothiocyanates, as required in other processes, is unnecessary. The amine used continues to give numerous possibilities of variation for the substituents. It has proven particularly expedient to carry out the cleavage of the 1,2,4-dithiazole-3-thione in the presence of metal salts, in which case metal complexes of the thioacylthioureas are formed directly. All compounds are obtained in high purity. ,

Exemplary embodiments Example 1

i-thiobenzoyl-3-morpholinothiohamstoff

2.11 g (0.01 mol) of 5-phenyl-1,2,4-dithiazole-3-thione are dissolved in about 50 ml of dichloromethane and slowly with ice cooling, a mixture of 2.66 g (0.01 mol) of triphenylphosphine and 0.87 g (0.01 mol) of morpholine in dichloromethane. After two hours of stirring, the solvent is removed in vacuo and the residue is shaken with a solution of 0.8 g (0.08 mol) of NaOH in 80 mol of methanol. After addition of twice the volume of ice water is filtered and the i-thiobehzoyl-3-morpholinothiourea precipitated with glacial acetic acid.

Yellow crystals, mp. 124 to 126 ⁰ C (chloroform / petroleum ether) yield 50%.

Further examples of this procedure are:

1-Thiobenzoyl-3,3-diethyl:

ocher mp. 80 to 83 ⁰ C in 35% yield

T-Thiobenzoyl-3-methyl-phenyl thiourea:

yellow m.p. 85 to 88 ° C 52% yield

1-thiobenzoyl-3- (2-pyridyl) thiourea:

yellow m.p. 113-115 ⁰ C 35% yield

Example 2

i-thiobenzoyl-3-phenylthiohamstoff

2.11 g (0.01 mol) of 5-phenyl-1,2,4-dithiazole-3-thione are dissolved in about 50 ml of tetrahydrofuran and slowly with ice cooling, a mixture of 2.66 g (0.01 mol) of triphenylphosphine and Added 9.3 g (0.01 mol) of aniline in tetrahydrofuran. After two hours of stirring, it is diluted with the same volume of water, the precipitate is filtered off with suction and shaken with a solution of 0.8 g (0.08 mol) of NaOH in 80 ml of methanol. After addition of twice the volume of ice water is filtered and the i-thiobenzoyl-3-anilinothiourea precipitated by the introduction of CO ₂ .

Yellow crystals, mp. 116-118 ° C (ethanol), yield 60%.

Bisd-thipbenzoyl-S-dibutylthioureate-nickKII) ' _: ^ \ ^;

2.11 g (0.01 mol) of 5 · ΡπβηγΜ, 2,4-αϊΐπϊ8ζρΙ. '' Ίπίοη are dissolved in 50ml · dichloromethah and added to 6g of a 6% solution of nickel octoate in gasoline. Under ice-cooling, a mixture of 2.60 g (0.01 mol) of triphenylphosphine and 1.3 g (0.01 mol) of dibutylamine in dichloromethane is added slowly. The nickel chelate formed is precipitated by addition of four times the amount of petroleum ether and digested several times with hot alcohol to remove adhering Tripnenyiphosphinsulfid. _:

Brown crystals, mp 130-131 ⁰ C (chloroform / ethanol), yield 70%. ,

Example 4

To d-thiobenzoyl S pyrrolidinothioureatol-cobaltdD

2.11 g (0.01 mol of 5-phenyl-1,2,4-dithiazole-3-thione are dissolved in 50 ml of dichloromethane and 6 g of an approximately 6% solution of cobalt naphthenate in petrol are added while cooling with ice Mixture of 2.60 g (0.01 mol) of triphenylphosphine and 7.1 g (0.01 mol) of pyrrolidine in dichloromethane The resulting cobalt chelate is precipitated by addition of four times the amount of petroleum ether and digested several times with hot alcohol to remove adhering triphenylphosphine sulfide ,

Brown crystal powder, mp 152-155 ° C (chloroform / ethanol), yield 50%.

Claims (4)

-3- 248 665 6 invention claims 1. A process for the preparation of 3-substituted thioacylthioureas of the formula I. Ri-CS-NH-CS-N R ^{1 is} alkyl, aryl or hetaryl R ² , R ^{3 are} hydrogen, alkyl, aryl, hetaryl, which may also be optionally mono- or polysubstituted by alkyl, alkoxy, halogen, nitro or cyano groups R ² and R ³ together with the connecting nitrogen atom and optionally with another heteroatom (O, S, N) form a 5 or 6 ring and their metal complexes with transition metals, characterized in that 1,2,4-dithiazole-3-thiones are cleaved with amines and triorganophosphines or phosphites in inert solvents at temperatures of -20 ° C to +50 ⁰ C. 2. Method according to item 1), characterized in that the cleavage of the 1,2,4-dithiazole-3-thione is carried out in the presence of complex-forming metal salts and leads directly to metal chelates of thioacylthioureas. 3. The method of item 1), characterized in that are used as amines primary and secondary alkyl, aryl or hetarylamines, as triorganophosphines and triorganophosphites alkyl or aryl compounds. 4. Process according to item 1), characterized in that aliphatic and aromatic hydrocarbons, halogenated or nitrohydrocarbons, cyclic and open-chain ethers are used as the inert solvent.