N-(3-bromo-1,1,1-trifluoropropan-2-ylidene)hydroxylamine

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

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

Procedure: To a suspension of KCN (1.90 g, 29.1 mmol) in MeOH (35 mL) was added dropwise 3-bromo-1,1,1-trifluoropropan-2-one oxime (5.00 g, 24.3 mmol) in MeOH (72 mL) at RT. The reaction mixture was stirred at RT for 3 hours. The solution was concentrated in vacuo, the residue was dissolved in EtOAc and stirred at RT. The solid was filtered and the filtrate was evaporated to obtain the crude product. The crude product was purified by silica gel column chromatography EtOAc/hexanes) to obtain 3-(trifluoromethyl)isoxazol-5-amine (1.38 g, 37% yield). MS (ESI) m/z: 153.0 (M+H+). The solution was concentrated in vacuo the residue was dissolved in EtOAc stirred at RT The solid was filtered the filtrate was evaporated to obtain the crude product The crude product was purified by silica gel column chromatography EtOAc/hexanes)

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

Procedure: To a suspension of KCN (1.90 g, 29.1 mmol) in MeOH (35 mL) was added dropwise 3-bromo-1,1,1-trifluoropropan-2-one oxime (5.00 g, 24.3 mmol) in MeOH (72 mL) at RT. The reaction mixture was stirred at RT for 3 hours. The solution was concentrated in vacuo, the residue was dissolved in EtOAc and stirred at RT. The solid was filtered and the filtrate was evaporated to obtain the crude product. The crude product was purified by silica gel column chromatography EtOAc/hexanes) to obtain 3-(trifluoromethyl)isoxazol-5-amine (1.38 g, 37% yield). MS (ESI) m/z: 153.0 (M+H+). The solution was concentrated in vacuo the residue was dissolved in EtOAc stirred at RT The solid was filtered the filtrate was evaporated to obtain the crude product The crude product was purified by silica gel column chromatography EtOAc/hexanes)

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

Procedure: To a solution of 2.5 g of 1-bromo-3,3,3-trifluoropropan-2-one in 15 mL of chloroform (passed through a pad of basic alumina) was added a solution of hydroxylamine hydrochloride in 2.5 mL of water and the mixture heated to reflux. After 25 hours, the reaction mixture was cooled and 15 mL of H2O was added. The layers were separated and the aqueous layer was washed with 3×15 mL dichloromethane. The combined organic extracts were dried over magnesium sulfate, filtered and concentrated in vacuo. Note: As the product is a volatile liquid, excessive application of the vacuum to remove the co-solvent reduced the yield of the product. it's the product was used without further purification. the mixture heated to reflux the reaction mixture was cooled The layers were separated the aqueous layer was washed with 3×15 mL dichloromethane The combined organic extracts were dried over magnesium sulfate filtered concentrated in vacuo to remove the co-solvent it's the product was used without further purification

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

Procedure: To a solution of 2.5 g of 1-bromo-3,3,3-trifluoropropan-2-one in 15 mL of chloroform (passed through a pad of basic alumina) was added a solution of hydroxylamine hydrochloride in 2.5 mL of water and the mixture heated to reflux. After 25 hours, the reaction mixture was cooled and 15 mL of H2O was added. The layers were separated and the aqueous layer was washed with 3×15 mL dichloromethane. The combined organic extracts were dried over magnesium sulfate, filtered and concentrated in vacuo. Note: As the product is a volatile liquid, excessive application of the vacuum to remove the co-solvent reduced the yield of the product. it's the product was used without further purification. the mixture heated to reflux the reaction mixture was cooled The layers were separated the aqueous layer was washed with 3×15 mL dichloromethane The combined organic extracts were dried over magnesium sulfate filtered concentrated in vacuo to remove the co-solvent it's the product was used without further purification

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

Procedure: To a solution of the 1.64 g (7.96 mmol) of 3-bromo-1,1,1-trifluoropropan-2-one oxime in 250 mL of methyl tert-butyl ether was added 3.74 g (31.92 mmol) of indole followed by 5.0 g (47.62 mmol) of powdered (freshly ground) sodium carbonate. The reaction was monitored by thin layer chromatography (ethyl acetate-hexanes (2:8)) to afford a new more polar product compared to indole (PMA-stained and UV-active). The mixture was then filtered through diatomaceous earth and concentrated in vacuo. The residue was then concentrated in vacuo and diluted first with dichloromethane (1 part) and then hexanes (4 parts) and passed through a pad of silica gel using dichloromethane-hexanes (gradient: 20%-100%) to afford 1.72 g (89.2%) of 1,1,1-trifluoro-3-(1H-indol-3-yl)propan-2-one oxime as a white solid. to afford a new more polar product The mixture was then filtered through diatomaceous earth concentrated in vacuo The residue was then concentrated in vacuo diluted first with dichloromethane (1 part)

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

Procedure: To a solution of 10.5 mL (102.3 mmol) of 1-bromo-3,3,3-trifluoropropan-2-one in 100 mL of chloroform (passed through a pad of basic Al2O3) was added a solution of 10.4 g (149.7 mmol) of hydroxylamine hydrochloride in 20 mL of water and the mixture was warmed at reflux. After 24 hours, the mixture was cooled and the organic phase was separated. The aqueous layer was extracted with three 30 mL portions of methylene chloride. The combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo to afford 11.5 g (55.7%) of 3-bromo-1,1,1-trifluoropropan-2-one oxime as a mixture (3:2) of geometric isomers. the mixture was warmed at reflux the mixture was cooled the organic phase was separated The aqueous layer was extracted with three 30 mL portions of methylene chloride The combined organic layers were dried over sodium sulfate filtered concentrated in vacuo

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

Procedure: To a solution of the 1.64 g (7.96 mmol) of 3-bromo-1,1,1-trifluoropropan-2-one oxime in 250 mL of methyl tert-butyl ether was added 3.74 g (31.92 mmol) of indole followed by 5.0 g (47.62 mmol) of powdered (freshly ground) sodium carbonate. The reaction was monitored by thin layer chromatography (ethyl acetate-hexanes (2:8)) to afford a new more polar product compared to indole (PMA-stained and UV-active). The mixture was then filtered through diatomaceous earth and concentrated in vacuo. The residue was then concentrated in vacuo and diluted first with dichloromethane (1 part) and then hexanes (4 parts) and passed through a pad of silica gel using dichloromethane-hexanes (gradient: 20%-100%) to afford 1.72 g (89.2%) of 1,1,1-trifluoro-3-(1H-indol-3-yl)propan-2-one oxime as a white solid. to afford a new more polar product The mixture was then filtered through diatomaceous earth concentrated in vacuo The residue was then concentrated in vacuo diluted first with dichloromethane (1 part)

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

Procedure: To a solution of 10.5 mL (102.3 mmol) of 1-bromo-3,3,3-trifluoropropan-2-one in 100 mL of chloroform (passed through a pad of basic Al2O3) was added a solution of 10.4 g (149.7 mmol) of hydroxylamine hydrochloride in 20 mL of water and the mixture was warmed at reflux. After 24 hours, the mixture was cooled and the organic phase was separated. The aqueous layer was extracted with three 30 mL portions of methylene chloride. The combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo to afford 11.5 g (55.7%) of 3-bromo-1,1,1-trifluoropropan-2-one oxime as a mixture (3:2) of geometric isomers. the mixture was warmed at reflux the mixture was cooled the organic phase was separated The aqueous layer was extracted with three 30 mL portions of methylene chloride The combined organic layers were dried over sodium sulfate filtered concentrated in vacuo

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

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

Procedure: To a suspension of KCN (1.90 g, 29.1 mmol) in MeOH (35 mL) was added dropwisely 3-bromo-1,1,1-trifluoropropan-2-one oxime (5.00 g, 24.3 mmol) in MeOH (72 mL) at RT. The reaction mixture was stirred at RT for 3 hours. The solution was evaporated and then the residue was dissolved in EtOAc and stirred at RT. The solid was filtered and the filtrate was evaporated to obtain the crude product. The crude product was purified by silica gel column chromatography (Biotage: 25M, 10% to 60% EtOAc/hexane: 550 mL) to obtain 3-(trifluoromethyl)isoxazol-5-amine (1.38 g, 37% yield). MS (ESI) m/z: 153.0 (M+H+). The solution was evaporated the residue was dissolved in EtOAc stirred at RT The solid was filtered the filtrate was evaporated to obtain the crude product The crude product was purified by silica gel column chromatography (Biotage: 25M, 10% to 60% EtOAc/hexane: 550 mL)

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

Procedure: To a solution of the 1.64 g (7.96 mmol) of 3-bromo-1,1,1-trifluoropropan-2-one oxime in 250 mL of methyl tert-butyl ether was added 3.74 g (31.92 mmol) of indole followed by 5.0 g (47.62 mmol) of powdered (freshly ground) sodium carbonate. The reaction was monitored by thin layer chromatography (ethyl acetate-hexanes (2:8)) to afford a new more polar product compared to indole (PMA-stained and UV-active). The mixture was then filtered through diatomaceous earth and concentrated in vacuo. The residue was then concentrated in vacuo and diluted first with dichloromethane (1 part) and then hexanes (4 parts) and passed through a pad of silica gel using dichloromethane-hexanes (gradient: 20%-100%) to afford 1.72 g (89.2%) of 1,1,1-trifluoro-3-(1H-indol-3-yl)propan-2-one oxime as a white solid. to afford a new more polar product The mixture was then filtered through diatomaceous earth concentrated in vacuo The residue was then concentrated in vacuo diluted first with dichloromethane (1 part)