SU1022970A1 - 2-alkyl/aryl/thioethylidene-1,1-diphosphonic acids or their potassium salts as collectors for flotation of cassiterite and method of producing them - Google Patents

Abstract

1., 2-Alkyl (aryl) thioethylidene-1, 1-diphosphonic acids or their potassium salts of the general formula h PO, T F - $ - SC Id 0 where with, R - K, or with R -) - CHa; or, R-H, as co-separators for cassiterite flotation. 2. A process for the preparation of 2-alkyl (aryl) -thioethylidene-1,1-diphosphonic acids or their potassium salts, which consists in the development of an alkylidene diphosphonic ibic acid that undergo interaction with tr ethylamine and thiol, - in molyomas of a ratio equal to d Is 1.7-3.0: 2.5-5, O, at 110g120s S in an acetic acid medium.

Description

ND Yu

CD The invention relates to the chemistry of organophosphorus compounds, namely to new 2-alkyl (aryl) -thioethylidene-1, 1-diphosphonic acids or their potassium salts of the general formula RS CKj-CH (ROhde with R - C Hj, R - K, or with R - (or which can be used as collectors for flotation of cassiterite. It is known to use 1-hydroxyoctylidene-1, 1-diphosphonic acid as collector for flotation of cassiterite. The closest to the invention in structure and purpose of NEC1 is 1- Hexyloxymethylene-1, 1-diphosphonic acid 23 However, this is the unity is sensitive to the temperature of the pulp, therefore flotation is mainly carried out at 30-35 ° C, a decrease in temperature drastically worsens flotation rates. The aim of the invention is to increase the efficiency of collectors for cassiterite flotation. The aim is to achieve the fact that the compounds of the general formula (I ), taken as a collector for flotation of cassiterite. A known assay for the preparation of alkyl thioethylidenephosphonates, containing. with the interaction of the corresponding number with vinylphosphonate in the presence of an alkali metal alcoholate .3. However, using this method it is not possible to obtain compounds of the general formula (I). The aim of the invention is to develop an accessible process for the preparation of 2-alkyl aryl} thioethylidene-1,1-d phosphonic acids or their potassium salts. The aim is achieved by the fact that according to the method for producing 2-alkyl (aryl) thioethylidene-1,1-diphos background acids or their potassium salts of the general formula (I), the vinylidene phosphonic acid is reacted with triethylamine and thiol, taken in a molar ratio equal to 1: 1.7-2.052.5-5.0, at 110120 ° C in an acetic acid medium. The possibility of introducing into this reaction the triethylammonium salts of non-limiting phosphorus acids in an acetic acid medium, as in the case under consideration, is not obvious, since it becomes impossible to catalyze alkali metal alkoxides, which will immediately be deactivated in the indicated medium. As a result of the rather high acidity of the medium concentration of the active nucleophile (RSJ will be extremely low. The occurrence of a negative charge on the phosphonate group as a result of salt formation should reduce the E-effect of the substituent and thereby reduce the activity of the double bond in relation to the nucleophilic addition reaction. Triethylamine in the proposed the method does not play the role of a catalytic base. Since the process proceeds in excess of acetic acid, the strongest base present in the mixture is an acetate-ion, which is several orders of magnitude less basic than triethylamine. For this reason, almost all of Triethylamine is in the form of a cation playing the role of an organophilic particle necessary to retain the High Polarity anions of vinylidene diphosphonic acid in a solution in the presence of low-polar thiols. simplicity of technology and allows to obtain the desired products with a quantitative yield. Example 1. A mixture of 3, O g of vinylidene diphosphonic acid hydrate, containing 2.80 g (14.9 mmol) of anhydrous substance, -3, 5 ml (25 mmol) of triethylamine, 6 ml of acetic acid and 4.6 g (37.3 mmol) -; benzylmercaptan is heated at 120 ° C 33 for 8 hours. After cooling, the contents are diluted with water, the excess benzylmercap- ' is removed by extraction with ether, s ..; are passed through a column with cation exchange resin KU-2 in H-form, eluted with water to neutrality, the Eluate is evaporated in vacuo, the residue, being 2-benzylthioethylidene-1,1-diphosphonic -acid (1), crystallizing; tc. 4.6 g of the expected product are obtained, the yield is about 100%. Pere, Cree: Steel is distilled from a mixture of Vinegar Acid and Ethyl acetate, Besvet1ch: needles, t. LbZ-167. Data pH-metric titration and elemental analysis. Found: eq 157.5; eq 104.0, 34.97, 34.57% C / 4.64, 4.67% H; 9.45, 10.10% S; 19.81, 19.77% R C H DOBEZ. Calculated. eq 156.1, 1, 34.62% C, 4.52 N; 10.27% S; 19.84% P PMR spectrum (), cG, ppm : 2,3-. 3j6, group of signals, ZN, Ctta.-CH,

3.9, singlet, 2H, CH. (Ph) i 7.5, singlet, 5H, CdH |.

Example 2. Analogously to example 1, the reaction of the triethylammonium salt of vinylidene diphosphonic acid with p-thiocresol is obtained with a yield of about 100% 2-p-tolylthioethylidene-1,1-diphosphonic acid (11) “After recrystallization from anhydrous acetic acid, t., Pl. 192-196, colorless small needles.

Data of pH-metric titration and elemental analysis.

Found) eq; 158.0} eq 105.5; 34.89, 34.73% with; 4.61, 4.69% H,

S N DOBRLZ

Calculated: equl156,1; eqz 34.62% with; 4.52% H; ,

PMR-spectrum () o m., 2 singlet, 3N, SN “2.4–4.0 group of signals, 3N, 7.1 and 7.5, asymmetrical doublets, 8 Hz, 4H,: aromatic protons.

EXAMPLE 3 Under conditions of example 3, out of 2.0 g of a hydride of vinylidene diphosphonic acid, containing 1.68 g (8.94 mmol) of anhydrous ethyl acetate, 3.6 ml (26 mmol) of triethylamine and MP (35, 7 mmol) butylmercaptan in 6 ml. anhydrous acetic acid gives 2, -5 g of 2-butylthioethylidene-1, 1-diphosphoric acid, g ota (III) as a non-crystalline glassy mass, yield about 100%. The acid (1I) is converted to a crystalline mono-potassium salt, as described in the previous example, "1 Data of pH-metric titration and elemental analysis.

Found 3KBj 325; eq 158.0, 19.41% P,

C HiijOfrPeSK.

Calculated 9KV {316.3, eq 158.2; R.

Monocalium salt (III).

Found,% 1 C 22.06) 21.91, H 4.94} 4.68; S, 9.63, 9.64.

Qe SOfiPg-K ..

in spelled,% s C 22.78} H 4.78, S 10.14.

Ex. 4. In laboratory conditions, a quartz-tourmaline-sulfide of ß-cassette type ore is subjected to flotation, using 2-arylthioethylidene-1,1-diphosphonic acid or their salts as collectors. ALA Comparison of the same ore sample has undergone flotation using. As a collector, 1-alkoxyalkyl iden-1, 1-diphosphonic acid and 1-oxyalkylidene-1,1-diphosphonic acid. The temperature of the pulp varies from 5-10 to 30.

The test results are shown in the table.

17,8

75.1

73.1 17.2 81.6 81.9

74.0

17.1

73.5 83.1 16.5 82.6

 15.864.7

35,815,183,6

Table continuation

Claims (2)

one. . 2-Alkyl (aryl) thioethylidene-1,1-diphosphonic acids or their potassium salts of the general formula where, at R-C4H9, R * -K, or at> or CH2- <5>, R - H, as collectors for flotation of cassiterite. 2. The method of obtaining 2-alkyl (aryl) thioethylidene-1,1-diphosphonic acids or their potassium salts, which consists in the fact that vinylidene diphosphonic acid is reacted with triethylamine and thiol taken in a molar ratio of Is1.7-3, 0: 2.5-5.0, at ^a 110g120 C in acetic acid medium.