Hydrochloric Acid → 1-[(Benzyloxy)carbonyl]azetidine-3-carboxylic acid

To a solution of 1-(tert-butoxycarbonyl)azetidine-3-carboxylic acid (3.00 g, 14.9 mmol) in MeOH (12.5 mL) was added 4M HCl in 1,4-dioxane (12.5 mL). The reaction was stirred at rt for 16 h. The mixture was evaporated to dryness. To a cooled (0° C.) solution of the residue in 1,4-dioxane (15 mL) and 2N aqueous NaOH (75 mL) was added benzyl chloroformate (2.67 g, 15.7 mmol), dropwise. The reaction was warmed to rt and was allowed to stir for 4 h. The mixture was washed with ethyl acetate (75 mL) and the aqueous layer was acidified (pH 5) with the addition of conc HCl. The mixture was extracted with ethyl acetate (3×75 mL) and the combined organic layers were washed with brine, dried (Na2SO4) and evaporated to give 2.10 g (60%) of the desired product. ES-MS m/z 235.90 [M+H]+, HPLC RT (min) 2.53.

1. customThe mixture was evaporated to dryness
2. temperatureTo a cooled (0° C.) solution of the residue in 1,4-dioxane (15 mL)
3. temperatureThe reaction was warmed to rt
4. stirringto stir for 4 h
5. washThe mixture was washed with ethyl acetate (75 mL)
6. additionwith the addition of conc HCl
7. extractionThe mixture was extracted with ethyl acetate (3×75 mL)
8. washthe combined organic layers were washed with brine
9. dry with materialdried (Na2SO4)
10. customevaporated

ORD record

ord-5b37111e75954858862dac0d8433d0d5

Source dataset

uspto-grants-2013_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08431695B2