1,1,2-trichloro-1,2,2-trifluoroethane

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

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: 2-Difluoromethyl-2-trifluoromethyl-1,3-dioxolane (50 g.) was placed in a 500 ml. flask along with 1,2,2-trifluoroperchloroethane (Freon 113) (425 ml.) and the solution cooled to -20° C. The mixture was fluorinated with 20% fluorine in argon at a fluorine rate of 0.1 mole per hour until about 1.5 moles of fluorine were added. An 8° (Centigrade) exotherm was observed during the reaction. The acidic mixture was stirred over K2CO3 until the vapors above the mixture no longer tested strongly acidic. The mixture was filtered and Freon 113 was stripped out of the filtrate, leaving 59 g. of crude product. By preparative chromatography pure 2-difluoromethyl-2-trifluoromethyl-4,4,5-trifluoro-1,3-dioxolane (12 g.) was isolated from the crude material. were added An 8° (Centigrade) exotherm was observed during the reaction The mixture was filtered leaving 59 g

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

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

Procedure: The present invention provides a process of preparing CTFE by continuously reacting 1,1,2-trichloro-1,2,2-trifluoroethane with zinc powder dispersed in an alkyl alcohol, the process is characterized by the steps of (a) connecting a plurality of reaction vessels each of which is provided with a stirrer to each other in a series arrangement such that when a liquid is continuously introduced into each reaction vessel the liquid overflows into the next reaction vessel, (b) continuously feeding a dispersion of zinc powder in an alkyl alcohol into only the first one of the plurality of reaction vessels to allow the dispersion in the first reaction vessel to overflow into the next reaction vessel and then into the remaining reaction vessels in turn while the stirrer of each reaction vessel is operated, (c) continuously feeding 1,1,2-trichloro-1,2,2-trifluoroethane into each of the reaction vessels while step (b) is performed thereby to form CTFE in each reaction vessel by continuous reaction of 1,1,2-trichloro-1,2,2-trifluoroethane with zinc powder to result in gradual conversion of zinc powder into zinc chloride, (d) continuously discharging CTFE from each reaction vessel while steps (b) and (c) are performed and collecting the discharged CTFE, and (e) continuously discharging a dispersion of the unreacted remainder of the zinc powder in a solution of zinc chloride in the alcohol from the last one of the plurality of reaction vessels while steps (b), (c) and (d) are performed.

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

Procedure: Under an atmosphere of nitrogen a solution of 1-isopropyl-1H-[1,2,4]triazole (19 mmol) in THF (50 mL) at −78° C. was treated with n-butyllithium (11.4 mL, 2.5 M, 28.5 mmol) dropwise giving a cream yellow suspension. Further n-butyllithium (3.8 mL, 2.5 M, 9.5 mmol) was added after 1 h and stirring continued for a further 1.5 h. 1,1,2-trichlorotrifluoroethane (4.57 mL, 38 mmol) was added dropwise giving a dark brown solution. The resultant reaction mixture was stirred for 15 min before being quenched by the addition of saturated aqueous NaHCO3 (20 mL) then allowed to warm to RT. The resultant mixture was extracted twice with diethyl ether, the combined organic extracts dried (Na2SO4), filtered and concentrated in vacuo to give 5-Chloro-1-isopropyl-1H-[1,2,4]triazole as a dark oil (3.9 g) which was used in the subsequent step without further purification. 1H NMR δ (ppm) (CDCl3): 7.85 (1H, s), 4.73-4.63 (1H, m), 1.54-1.46 (6H, m). dropwise giving a cream yellow suspension giving a dark brown solution The resultant reaction mixture was stirred for 15 min before being quenched by the addition of saturated aqueous NaHCO3 (20 mL) The resultant mixture was extracted twice with diethyl ether the combined organic extracts dried (Na2SO4) filtered concentrated in vacuo

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

Procedure: Under an atmosphere of nitrogen a solution of 1-isopropyl-1H-[1,2,4]triazole (19 mmol) in THF (50 mL) at −78° C. was treated with n-butyllithium (11.4 mL, 2.5 M, 28.5 mmol) dropwise giving a cream yellow suspension. Further n-butyllithium (3.8 mL, 2.5 M, 9.5 mmol) was added after 1 h and stirring continued for a further 1.5 h. 1,1,2-trichlorotrifluoroethane (4.57 mL, 38 mmol) was added dropwise giving a dark brown solution. The resultant reaction mixture was stirred for 15 min before being quenched by the addition of saturated aqueous NaHCO3 (20 mL) then allowed to warm to RT. The resultant mixture was extracted twice with diethyl ether, the combined organic extracts dried (Na2SO4), filtered and concentrated in vacuo to give 5-Chloro-1-isopropyl-1H-[1,2,4]triazole as a dark oil (3.9 g) which was used in the subsequent step without further purification. 1H NMR δ (ppm) (CDCl3): 7.85 (1H, s), 4.73-4.63 (1H, m), 1.54-1.46 (6H, m). dropwise giving a cream yellow suspension giving a dark brown solution The resultant reaction mixture was stirred for 15 min before being quenched by the addition of saturated aqueous NaHCO3 (20 mL) The resultant mixture was extracted twice with diethyl ether the combined organic extracts dried (Na2SO4) filtered concentrated in vacuo

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

Procedure: A mixture of 1,1,2-trichlorotrifluoroethane (X) (9.37 g, 50 mmol), vinylidene chloride (4.85 g, 50 mmol), ammonium persulfate (11.41 g, 50 mmol), sodium formate (3.4 g, 50 mmol) and water (1.8 g, 0.1 mol) in DMF (80 mL) was stirred (dry-ice/acetone condensor) at room temperature with air bubbling. After 30 min, an aliquot of the reaction mixture was acidified with dilute HCl, extracted with ether and analyzed by GC, which indicated the formation of two products. These products were identified by GC/MS (EI) as 4-chloro-3,4,4-trifluoro-2-butenoic acid and novel compound 3,4-dichloro-3,4,4-trifluorobutanoic acid (XI). The compound XI gives 3,4,4-trifluoro-3-butenoic acid (IV) upon reaction with zinc. Under the above reaction conditions, 1-chloro-1,2-dibromotrifluoroethane (VI) gave 3-chloro-4-bromo-3,4,4-trifluorobutanoic acid (VIII) as one of the products. bubbling extracted with ether

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

Procedure: A one pot reaction of 1-chloro-1,2-dibromotrifluoroethane (VI) or 1,1,2-trichlorotrifluoroethane (X) with vinylidene chloride in the presence of ammonium persulfate/sodium formate/air in DMF to give 4-bromo-3-chloro-3,4,4-trifluorobutanoic acid (VIII) or 3,4- dichloro-3,4,4-trifluorobutanoic acid (XI).

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

Procedure: A one pot reaction of 1-chloro-1,2-dibromotrifluoroethane (VI) or 1,1,2-trichlorotrifluoroethane (X) with vinylidene chloride in the presence of ammonium persulfate/sodium formate/air in DMF to give 4-bromo-3-chloro-3,4,4-trifluorobutanoic acid (VIII) or 3,4- dichloro-3,4,4-trifluorobutanoic acid (XI).

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

Procedure: A mixture of 1,1,2-trichlorotrifluoroethane (X) (9.37 g, 50 mmol), vinylidene chloride (4.85 g, 50 mmol), ammonium persulfate (11.41 g, 50 mmol), sodium formate (3.4 g, 50 mmol) and water (1.8 g, 0.1 mol) in DMF (80 mL.) was stirred (dry-ice/acetone condensor) at room temperature with air bubbling. After 30 min, an aliquot of the reaction mixture was acidified with dilute HCl, extracted with ether and analyzed by GC, which indicated the formation of two products. These products were identified by GC/MS (EI) as 4-chloro-3,4,4-trifluoro-2-butenoic acid and novel compound 3,4-dichloro-3,4,4-trifluorobutanoic acid (XI). The compound XI gives 3,4,4-trifluoro-3-butenoic add (IV) upon reaction with zinc. Under the above reaction conditions, 1-chloro-1,2-dibromotrifluoroethane (VI) gave 3-chloro-4-bromo-3,4,4-trifluorobutanoic acid (VIII) as one of the products. bubbling extracted with ether