SU1648948A1 - Method for obtaining of 2-mercaptobenzooxasoles - Google Patents

Abstract

The invention relates to heterocyclic substances, in particular the preparation of 2-mev-captobenzoxazoles of the total phyla I CH CRi-CH CH-C C-N-C (SH) 9. where Ri is H, halogen, CH3, N02. used in the synthesis of pesticides. The goal is to reduce the cost and intensify the process while reducing reagent consumption and expanding the resource base. Synthesis is carried out by the reaction of 2-aminophenol with a dithiocarbamic acid derivative of the total f-ly II or III ((S) -SM (II), (R2) 2N-C (S) -SSC (S) -N (R2) 2 (III) where R2 is CH3 or C2Hs; M is an alkali metal, moreover, when M is sodium, the compound of phase II and 2-aminophenol is taken in an equilibrium ratio and the process takes 2-2.5 hours. When using compound f- ly III takes its molar ratio with 2-aminophenol (1.2-1.3): 2 and the process is carried out in water, methanol or ethanol 0.3-1.5 hours. These conditions increase the yield of the target substances to 90-97% while reducing the consumption of dithiocarbamic acid derivatives and 12% and the duration of the process for 0.5-4 hours. z.p.f- ly 2, Table 7.

Description

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1648948

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Claims (3)

Claim 1. The method of obtaining 2-mercaptobenzoxazoles of the general formula I where Ri is hydrogen, halogen, methyl or nitro group, by heating the corresponding o-aminophenol with a sulfur-containing reagent in the presence of a solvent, characterized in that, in order to reduce the cost and intensify the process, save reagents and expand the raw material base of the target products, take o-aminophenol of the general formula II, ^he r / ^ nh ₂ where Ri has the indicated meanings, and a dithiocarbamic acid derivative of the general formula Hi or IV is taken as a sulfur-containing reagent R ₂ x V S N-C-S-M where R2 is a methyl or ethyl group; M is an alkali metal. 2. The method of pop. 1, characterized in that they take an o-aminophenol of formula II and a dithiocarbamic acid derivative of formula III, where M is sodium, in a molar ratio of 1: 1 and the reaction is carried out for 2-2.5 hours. 3. The method of pop. 1, characterized in that. that they take o-aminophenol of formula II and a dithiocarbamic acid derivative of formula IV in a molar ratio of 2: (1.21.3), respectively, water, methanol or ethanol are taken as solvent and the reaction is carried out at a boiling point of the mixture for 0.3-1 5 hours Table 1 Experience Synthesis of 5-B-2-mercaptobenzoxazals R Reaction time, h Exit, % Melting point, ° C 1 N 2.5 95.5 193-195 2 SNZ 2,5 94.2 221-223 3 Ci 2,5 92.6 267-269 4 Vg 2,5 91.8 276-278, 14 N 2,5 96.0 193-195 fifteen Ci 2,5 94.8 267-269 16 Vg 2,5 92.4 276-278 17 N 1 94 193-195 18 SNZ 1 95.4 221-223 19 Ci 1 90,4 267-269 20 Vg 1 96.8 276-278 21 N02 0.5 91.1 228-231 table 2 Experience Reaction time, h The yield of 2-mercaptobenzoxazole,% 5 1 80.8 6 1,5 86.1 1 2 95.5 7 2,5 95.4 8 3 95.4 Table 3 Experience Solvent The yield of 2-mercaptobenzoxazole,% 1 H ₂ O 95.5 9 DMF 90.5 10 Ethanol 89.0 eleven Propanol-1 82.0 Table 4 Experience The ratio of o-aminophenol: sodium diethyldithiocarbamate, mol Exit, % 12 0.01: 0.009 86 1 0.01: 0.01 95.5 thirteen 0.01: 0.011 95.6 Table 5 Experience Reaction time, h Exit, % 22 0.25 86.1 23 0.5 90.1 24 0.75 94.0 17 1 94.0 25 1.25 83,2 26 1,5 46,4 Table 6 Experience o-aminophenol, mole tmtd, mol The molar ratio of oaminophenol: TMTD Exit, % 27 0.01 0.005 2: 1 56.3 28 0.01 0.0055 2: 1.1. 75.5 17 0.01 0.006 2: 1.2 94.0 29th 0.01 0.0065 2: 1.3 90.8 thirty 0.01 0.007 2: 1.4 90.1 Table 7 Experience Solvent Reaction time, h Exit, % 35 SNzone 0.5 82.2 36 SNzone 1,0 92.1 31 SNzone 1,5 95.4 37 SNzone 2.0 90.2 17 S2N5ON 1,0 94.0 32 N-S3N7ON 0.25 80.2 38 H2O 0.25 83.6 33 H ₂ O 0.30 97.5 39 H ₂ O 0.5 90.1 40 H ₂ O 1.0 88.8