3-bromopentan-2-one

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of the tetrabutylammonium salt of 4-amino-5-chloro-N-[2-(diethylamino)ethyl]-2-hydroxybenzamide (10.5 g, 20 mmoles) (from Prepration No. 3) in acetonitrile (150 ml) was treated with 3-bromo-2-pentanone (3.3 g of 80%, 20 mmoles, contaminated with 15% of 1-bromo-2-pentanone) [obtained according to the procedure of E. T. Borrows, D. O. Holland and J. Kenyon, J. Chem. Soc. 1083, (1946)]. After 3 hours, the solvent was evaporated and the residue partitioned between ethyl acetate and water. The organic phase was washed with water, dried, and the solvent evaporated. The semisolid residue was triturated with ether to yield a solid which was recrystallized from ether--petroleum ether to yield 1.5 g of the title compound, mp. 75°-78°. The NMR spectrum (90 MHz) in CDCl3 gave the following resonances: δ 8.26 (s, 1H); 8.14 (bs, 1H); 6.1 (s, 1H); 4.5 (t, 1H); 4.4 (s, 2H); 3.69 (q, 2H); 2.64 (m, 6H); 2.1 (s, 3H); 2.1-1.7 (m, 2H); 1.05 (m, 9H). obtained the solvent was evaporated the residue partitioned between ethyl acetate and water The organic phase was washed with water dried the solvent evaporated The semisolid residue was triturated with ether to yield a solid which was recrystallized from ether

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 11.2 g of potassium tert-butylate, dissolved in 100 ml of dry tetrahydrofuran, are initially introduced into the reaction vessel at room temperature. 11.4 g of furfurylmercaptan are added dropwise at 20° C. When the addition is complete, the mixture is subsequently stirred for a further 30 minutes. 16.5 g of 3-bromopentan-2-one are then added dropwise in the course of 30 minutes and the mixture is subsequently stirred for one hour. For working up, the mixture is poured onto 100 ml of water and extracted twice with diethyl ether, and the combined organic phases are washed with water, dried over sodium sulphate and concentrated. 19 g of crude product (purity 84.1%) are obtained. For further purification, the product is subjected to bulb tube distillation. 10 g of 3-furfurylthio-pentan-2-one, which has a purity of 97.5%, are obtained. The IR, NMR and mass spectra of the compound agree with the structure described for it. are initially introduced into the reaction vessel at room temperature When the addition the mixture is subsequently stirred for one hour extracted twice with diethyl ether the combined organic phases are washed with water dried over sodium sulphate concentrated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of the tetrabutylammonium salt of 4-amino-5- chloro-N-[2-(diethylamino)ethyl]-2-hydroxybenzamide (10.5 g, 20 mmoles) (from Preparation No. 3) in acetonitrile (150 ml) was treated with 3-bromo-2-pentanone (3.3 g of 80%, 20 mmoles, contaminated with 15% of 1-bromo-2-pentanone) [obtained according to the procedure of E. T. Borrows, D. O. Holland and J. Kenyon, J. Chem. Soc. 1083, (1946)]. After 3 hours, the solvent was evaporated and the residue partitioned between ethyl acetate and water. The organic phase was washed with water, dried, and the solvent evaporated. The semisolid residue was triturated with ether to yield a solid which was recrystallized from etherpetroleum ether to yield 1.5 g of the title compound, mp. 75°-78°. The NMR spectrum (90 MHz) in CDCl3 gave the following resonances: δ8.26 (s, 1H); 8.14 (bs, 1H); 6.1 (s, 1H); 4.5 (t, 1H); 4.4 (s, 2H); 3.69 (q, 2H); 2.64 (m, 6 H); 2.1 (s, 3H); 2.1-1.7 (m, 2H); 1.05 (m, 9H). obtained the solvent was evaporated the residue partitioned between ethyl acetate and water The organic phase was washed with water dried the solvent evaporated The semisolid residue was triturated with ether to yield a solid which was recrystallized from etherpetroleum ether

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 2,4-dihydro-4-[4-[4-(4-methoxyphenyl)-1-piperazinyl]phenyl]-3H-1,2,4-triazol-3-one (0.05 mol) prepared as described in Eβ-A-0,006,711, 3-bromo-2-pentanone (0.073 mol) and K2CO3 (10 g) in DMF (200 ml) and toluene (200 ml) was stirred and refluxed overnight using a water separator. The solvent was evaporated. The residue was dissolved in CH2Cl2. The organic solution was washed, dried, filtered and the solvent was evaporated. The residue was crystallized from 2-propanol. The precipitate was filtered off and the filtrate was evaporated. The residue was triturated in DIPE, filtered off and dried, yielding 4.6 g of (±)-2-(1-ethyl-2-oxopropyl)-2,4-dihydro-4-[4-[4-(4-methoxyphenyl)-1-piperazinyl]phenyl]-3H-1,2,4-triazol-3-one (intermn. prepared refluxed overnight The solvent was evaporated The residue was dissolved in CH2Cl2 The organic solution was washed dried filtered the solvent was evaporated The residue was crystallized from 2-propanol The precipitate was filtered off the filtrate was evaporated The residue was triturated in DIPE filtered off dried

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of the tetrabutylammonium salt of 4-amino-5-chloro-N-[2-(diethylamino)ethyl]-2-hydroxybenzamide (10.5 g, 20 mmoles) (from Prepration No. 3) in acetonitrile (150 ml) was treated with 3-bromo-2-pentanone (3.3 g of 80%, 20 mmoles, contaminated with 15% of 1-bromo-2-pentanone) [obtained according to the procedure of E. T. Borrows, D. O. Holland and J. Kenyon, J. Chem. Soc. 1083, (1946)]. After 3 hours, the solvent was evaporated and the residue partitioned between ethyl acetate and water. The organic phase was washed with water, dried, and the solvent evaporated. The semisolid residue was triturated with ether to yield a solid which was recrystallized from ether--petroleum ether to yield 1.5 g of the title compound, mp. 75°-78°. The NMR spectrum (90 MHz) in CDCl3 gave the following resonances: δ 8.26 (s, 1H); 8.14 (bs, 1H); 6.1 (s, 1H); 4.5 (t, 1H); 4.4 (s, 2H); 3.69 (q, 2H); 2.64 (m, 6H); 2.1 (s, 3H); 2.1-1.7 (m, 2H); 1.05 (m, 9H). obtained the solvent was evaporated the residue partitioned between ethyl acetate and water The organic phase was washed with water dried the solvent evaporated The semisolid residue was triturated with ether to yield a solid which was recrystallized from ether