(2R)-1-[tert-butyl(dimethyl)silyl]oxypropan-2-amine

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

Procedure: A procedure similar to that described in Preparation 9 was repeated, except that 16.4 g of benzyl N-[2-t-butyldimethylsilyloxy-1(R)-methylethyl]carbamate (prepared as described in Preparation 24), 3.5 g of 10% w/w palladium-on-carbon and 100 ml of ethanol were used, to give 8.55 g of the title compound having an Rf value of 0.27 (on silica gel thin layer chromatography, using a 1:3 by volume mixture of ethyl acetate and hexane as the developing solvent) and having [α]D =-10.1° (methanol, c=1.155). A procedure similar to that described in Preparation 9

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

Procedure: A procedure similar to that described in Preparation 9 was repeated, except that 16.4 g of benzyl N-[2-t-butyldimethylsilyloxy-1(R)-methylethyl]carbamate (prepared as described in Preparation 24), 3.5 g of 10% w/w palladium-on-carbon and 100 ml of ethanol were used, to give 8.55 g of the title compound having an Rf value of 0.27 (on silica gel thin layer chromatography, using a 1:3 by volume mixture of ethyl acetate and hexane as the developing solvent) and having [α]D =-10.1° (methanol, c=1.155). A procedure similar to that described in Preparation 9

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

Procedure: A procedure similar to that described in Preparation 9 was repeated, except that 16.4 g of benzyl N-[2-t-butyldimethylsilyloxy-1(R)-methylethyl]carbamate (prepared as described in Preparation 24), 3.5 g of 10% w/w palladium-on-carbon and 100 ml of ethanol were used, to give 8.55 g of the title compound having an Rf value of 0.27 (on silica gel thin layer chromatography, using a 1:3 by volume mixture of ethyl acetate and hexane as the developing solvent) and having [α]D =-10.1° (methanol, c=1.155). A procedure similar to that described in Preparation 9

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

Procedure: A mixture of (R)-2-(tert-butyl-dimethyl-silanyloxy)-1-methyl-ethylamine (693 mg, 3,66 mmol) (from Example 38a supra) and triethylamine (0.77 mL, 5.5 mmol) (Allied Signal) in dichloromethane was treated with 4-nitrophenyl chloroformate (885 mg, 4.39 mmol) (Aldrich) at room temperature for 30 minutes. The reaction was quenched with 1 N aqueous hydrochloric acid and then extracted with ethyl acetate. The combined organic layers were washed with saturated aqueous sodium bicarbonate solution followed with brine, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by flash chromatography (15% ethyl acetate in hexanes) to give (R)-[2-(tert-butyl-dimethyl-silanyloxy)-1-methyl-ethyl]-carbamic acid 4-nitro-phenyl ester as a colorless oil that solidified upon standing. (Yield 0.49 g, 38%). The reaction was quenched with 1 N aqueous hydrochloric acid extracted with ethyl acetate The combined organic layers were washed with saturated aqueous sodium bicarbonate solution dried over anhydrous sodium sulfate filtered concentrated under reduced pressure The crude product was purified by flash chromatography (15% ethyl acetate in hexanes)

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

Procedure: D-Alaninol hydrochloride (500 mg, 6.66 mmol) (Aldrich) was dissolved in anhydrous dimethylformamide (10 mL) (Aldrich). Imidazole (544 mg, 8 mmol) (Aldrich) and tert-butyldimethylsilyl chloride (1.05 g, 7 mmol) (Aldrich) were successively added at room temperature. This mixture was stirred at room temperature for 2 hours, quenched with a solution of water-saturated aqueous sodium bicarbonate solution (5:1, 15 mL) and extracted with ethyl acetate. The organic layer was washed with water and brine, dried over sodium sulfate, and concentrated under reduce pressure to yield (R)-2-(tert-butyl-dimethyl-silanyloxy)-1-methyl-ethylamine as a colorless oil. (Yield 852 mg, 68%). quenched with a solution of water-saturated aqueous sodium bicarbonate solution (5:1, 15 mL) extracted with ethyl acetate The organic layer was washed with water and brine dried over sodium sulfate concentrated