triethyl borate

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:-20.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of tetradecylmagnesium chloride (50 ml, 1M in THF) was added at −20° C. to THF (50 ml) followed by triethyl borate (10.2 ml, 60 mmol). The reaction mixture was stirred briefly at −20° C., and warmed up slowly over 3 hours to room temperature. Most of the solvent was removed on rotary evaporator and the concentrated mixture was poured into water (300 ml) and pH of the mixture was adjusted to about pH 4 using 12N hydrochloric acid. After being stirred for 10 hours, precipitated tetradecylboronic acid was isolated by filtration, washed three times with water and dried with air overnight. The dried white solid was washed with cold hexane to remove a trace of tetradecane and dried with air to yield 11.3 g (93%) of n-tetradecylboronic acid. warmed up slowly over 3 hours to room temperature Most of the solvent was removed on rotary evaporator the concentrated mixture was poured into water (300 ml) After being stirred for 10 hours precipitated tetradecylboronic acid was isolated by filtration washed three times with water dried with air overnight The dried white solid was washed with cold hexane to remove a trace of tetradecane dried with air

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 1-bromo-2-(isopentyloxy)benzene (9.68 g, 40 mmol) in THF (160 mL) was added dropwise n-butyl lithium (1.6 M in hexanes, 1.05 eq., 26.3 mL) under nitrogen at −78° C. over 30 min. After further stirring for 1 hour at −78° C., triethylborate (5.86 mL, 51.3 mmol) was added. The cooling bath was removed and the reaction mixture was stirred overnight at rt. An aqueous solution of 2 N HCl (20 mL) was added and the reaction solution stirred for 30 min, at which point 50 mL of water was added. The reaction mixture was extracted with ether (5×80 mL), dried over anhydrous sodium sulfate, filtrated and concentrated to yield 2-(isopentyloxy)phenylboronic acid (6.30 g, 77% yield). 1H NMR (400 MHz, CDCl3): 7.83 (d, 1H), 7.43 (dd, 1H), 7.03 (t, 1H), 6.93 (d, 1H), 6.05 (s, 2H), 4.10 (t, 2H), 1.86-1.75 (m, 3H), 1.0 (s, 6H). The cooling bath was removed the reaction mixture was stirred overnight at rt An aqueous solution of 2 N HCl (20 mL) was added the reaction solution stirred for 30 min, at which was added The reaction mixture was extracted with ether (5×80 mL) dried over anhydrous sodium sulfate filtrated concentrated

Conditions: temp:-70.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 100 ml of a solution of 10 g of p-bromoanisole in anhydrous diethyl ether is added dropwise under reflux to a suspension, under inert gas, of 1.3 g of magnesium turnings in 5 ml of anhydrous diethyl ether, and the mixture is left under reflux for 2 hours. The reaction medium is then poured into a solution of 9.02 ml of triethylborate in 60 ml of anhydrous ether cooled down to −70° C. After agitation for 1 hour at −70° C., then for 1 hour at ambient temperature, the solution is poured into a mixture comprising 11 ml of sulphuric acid and 50 g of ice and water followed by agitation for 1 hour. The organic phase is extracted with 100 ml of an aqueous solution saturated in sodium bicarbonate, the aqueous phases are combined, then reacidified with 6N hydrochloric acid, extracted with ether, dried and evaporated under reduced pressure. 3.9 g of expected product is obtained. the mixture is left under reflux for 2 hours for 1 hour at ambient temperature followed by agitation for 1 hour The organic phase is extracted with 100 ml of an aqueous solution saturated in sodium bicarbonate extracted with ether dried evaporated under reduced pressure

Conditions: temp:-70.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 100 ml of a solution of 10 g of p-bromoanisole in anhydrous diethyl ether were added dropwise at reflux under an inert gas atmosphere to a suspension of 1.3 g of Mg turnings in 5 ml of anhydrous diethyl ether, and the mixture was refluxed for 2 hours. The mixture was then poured into a solution of 9.02 ml of triethylborate in 60 ml of anhydrous ether cooled to -70° C. After stirring for one hour at -70° C., then for one hour at ambient temperature, the solution was poured into a mixture of 11 ml of sulfuric acid and 50 g of ice and water and stirring was carried out for one hour. The organic phase was extracted with 100 ml of a saturated aqueous solution of sodium bicarbonate and the aqueous phases were combined and reacidified with 6N hydrochloric acid, followed by extraction with ether, drying and evaporating under reduced pressure to obtain 3.9 g of the expected product. the mixture was refluxed for 2 hours for one hour at ambient temperature stirring was carried out for one hour The organic phase was extracted with 100 ml of a saturated aqueous solution of sodium bicarbonate followed by extraction with ether drying evaporating under reduced pressure

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Under a nitrogen atmosphere, 16.70 g (52.00 mmol) of 5-benzyloxy-2-bromo-4-ethyl-1-methoxybenzene (4) was added to 110 mL of anhydrous THF. The solution was cooled to −78° C., and 22.88 mL (57.19 mmol) of a 2.5 M solution of butyl lithium was added dropwise while maintaining the temperature below −70° C. The reaction mixture was stirred at −78° C. for 45 minutes. 9.73 mL (57.19 mmol) of triethyl borate was then added, and the reaction was allowed to stir at −78° C. for an additional 2 hours. The reaction mixture was then allowed to warm to 23° C. over a 30 minute period and was quenched with 100 mL of saturated NH4Cl. The pH was adjusted to 5.0 with 1M HCl, and the resultant solution was extracted with ethyl acetate (2×200 mL). The combined extracts were washed with brine (1×100 mL), dried over sodium sulfate, filtered and concentrated in vacuo to yield crude product as a greenish-tan solid. The crude product was triturated with hexane and filtered to afford 10.65 g (64%) of 4-benzyloxy-5-ethyl-2-methoxy-phenylboronic acid (5) as an off-white solid. while maintaining the temperature below −70° C to stir at −78° C. for an additional 2 hours to warm to 23° C. over a 30 minute period was quenched with 100 mL of saturated NH4Cl the resultant solution was extracted with ethyl acetate (2×200 mL) The combined extracts were washed with brine (1×100 mL) dried over sodium sulfate filtered concentrated in vacuo to yield crude product as a greenish-tan solid The crude product was triturated with hexane filtered

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The resulting 5-benzyloxy-2-bromo-4-ethyl-1-methoxybenzene (4) is allowed to react with n-butyl lithium in a polar solvent such as ether, glyme or tetrahydrofuran (THF), preferably THF, at a temperature of about −78° C. Triethyl borate is then added to the reaction mixture, and the reaction mixture is allowed to stir at a temperature of about −78° C. The reaction mixture is then allowed to warm to about room temperature. The reaction yields 4-benzyloxy-5-ethyl-2-methoxy-phenylboronic acid (5). to warm to about room temperature

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

Procedure: To a solution of 4-benzo[c]furazanyl bromide (4 g, 0.020 mol) in tetrahydrofurane (80 ml) and n-pentane (20 ml) is added triethylborate (3.8 ml, 0.022 mol) and N,N,N,N-tetraethylendiamine (3 ml, 0.02 mol). Then, n-BuLi (8.8 ml, 2.5N in hexane, 0.022 mol) is added dropwise at -100° C. and the solution is stirred for 5 minutes more. The reaction mixture is poured into an aqueous solution of saturated ammonium chloride and the water phase is extracted with ethyl acetate. The organic solvent is removed and the crude product is taken up in dichloromethan/n-hexane (5:6). The suspension is filtered to yield the title compound (1.05 g) which is used without further purification. the water phase is extracted with ethyl acetate The organic solvent is removed The suspension is filtered

Conditions: temp:-70.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Then, 6.6 g of 4-bromo-2-ethyl-6-methyl-1-[3-(4-trifluoromethoxyphenoxy)propyloxy]benzene was dissolved in 200 ml of tetrahydrofuran, and the solution was stirred at -70° C., to which 9.6 ml of n-butyl lithium solution (in hexane, 1.58 mol/liter) was added dropwise, followed by further stirring at -70° C. for 2 hours. To this reaction mixture was added dropwise a solution of 2.2 g of triethoxy borane dissolved in 60 ml of tetrahydrofuran. Then, the reaction mixture was stirred for 1 hour, while warming to room temperature, and 13 ml of 10% aqueous hydrochloric acid solution was added in small portions, followed by stirring at room temperature for 20 minutes. The tetrahydrofuran layer was washed with water, dried with anhydrous magnesium sulfate, and concentrated, to which 50 ml of toluene was added, and the mixture was heated at 70° C. under stirring, to which 6 ml of 30% aqueous hydrogen peroxide solution was added dropwise. The mixture was heated under reflux for 1 hour, and washed once with water, twice with 10% aqueous ammonium ferrous sulfate solution, and once with water. The toluene layer was dried with anhydrous magnesium sulfate, and concentrated to obtain a crude product. The crude product was subjected to silica gel chromatography, which afforded 3.4 g of 3-ethyl-4-[3-(4-trifluoromethoxyphenoxy)propyloxy]-5-methylphenol (61% yield), nD25.4 1.4955. was added dropwise Then, the reaction mixture was stirred for 1 hour while warming to room temperature by stirring at room temperature for 20 minutes The tetrahydrofuran layer was washed with water dried with anhydrous magnesium sulfate concentrated, to which 50 ml of toluene was added the mixture was heated at 70° C. under stirring, to which 6 ml of 30% aqueous hydrogen peroxide solution was added dropwise The mixture was heated under reflux for 1 hour washed once with water, twice with 10% aqueous ammonium ferrous sulfate solution The toluene layer was dried with anhydrous magnesium sulfate concentrated to obtain a crude product

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

Procedure: To a solution of 3,5-dimethoxybenzyl alcohol (2.71 g) in tetrahydrofuran (50 mL) was added n-butyllithium (1.56M hexane solution; 36.2 mL)while cooling with ice with ice bath, and the internal temperature was raised to room temperature and stirred for 1 hour. The internal temperature was then cooled to −78° C., to the mixture was added triethoxyborane (9.6 mL), and the temperature was raised to room temperature while stirring. After completion of the reaction, saturated aqueous ammonium chloride was added to the reaction mixture while cooling with ice and the reaction mixture was extracted with ethyl acetate, and then after washing the organic extract with brine, it was dried over anhydrous magnesium sulfate and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (50 g) and the title compound (1.72 g) was obtained as a white amorphous solid from the ethyl acetate fraction. while cooling with ice with ice bath The internal temperature was then cooled to −78° C., to the mixture the temperature was raised to room temperature while stirring was added to the reaction mixture while cooling with ice the reaction mixture was extracted with ethyl acetate after washing the organic extract with brine, it was dried over anhydrous magnesium sulfate the solvent was evaporated under reduced pressure The residue was purified by silica gel column chromatography (50 g)