2-amino-2-(4-iodophenyl)ethanol

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:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of lithium borohydride in THF (25.1 ml, 2 M solution) under an argon atmosphere was added dropwise chlorotrimethylsilane (12.7 ml). To the resulting suspension was added portionwise (RS)-amino-(4-iodo-phenyl)-acetic acid hydrochloride (6.30 g). Stirring was continued for 4 h and then the mixture was cooled to 0° C. and quenched by dropwise addition of methanol (4.5 ml). After stirring for 15 min at room temperature, water was added and the mixture was then diluted with ethyl acetate. Saturated brine was then added and the aqueous phase made alkaline (pH 14) by addition of 5 N aq NaOH. The phases were separated and the organic phase was washed with saturated brine and then dried over sodium sulphate and concentrated in vacuo to afford (RS)-2-amino-2-(4-iodo-phenyl)-ethanol (5.27 g, quant.) as a yellow solid. MS (ISP): 264.1 ([M+H]+). quenched by dropwise addition of methanol (4.5 ml) After stirring for 15 min at room temperature water was added the mixture was then diluted with ethyl acetate Saturated brine was then added by addition of 5 N aq NaOH The phases were separated the organic phase was washed with saturated brine dried over sodium sulphate concentrated in vacuo

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

Procedure: To a mixture of the compound (4.70 g) obtained in step (3) above, 4-dimethylaminopyridine (48.2 mg), triethylamine (4.40 mL) and chloroform (63.2 mL), a solution of tert-butyldimethylchlorosilane (2.38 g) in chloroform (31.6 mL) was added dropwise under cooling with ice and the mixture was stirred at the same temperature for 30 minutes, and then at room temperature for three days. The reaction mixture was concentrated under reduced pressure and water and ethyl acetate were then added. Extraction was conducted with ethyl acetate and the combined organic layers were dried over anhydrous magnesium sulfate. The desiccant was removed by filtration and the filtrate was concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (chloroform:methanol=100:0-98:2) to give the titled compound as a pale yellow oil (4.68 g). under cooling with ice at room temperature for three days The reaction mixture was concentrated under reduced pressure and water and ethyl acetate were then added Extraction the combined organic layers were dried over anhydrous magnesium sulfate The desiccant was removed by filtration the filtrate was concentrated under reduced pressure The resulting residue was purified by silica gel column chromatography (chloroform:methanol=100:0-98:2)