Reaction #72091

Reaction equation

Methanol

hydrochloric acid ethyl acetate

tert-butyl cis(±)-4-{[(benzyloxy)carbonyl]amino}-3-methoxypiperidine-1-carboxylate

Chloroacetyl chloride

→

title compound

Benzyl cis(±)-[1-(chloroacetyl)-3-methoxypiperidin-4-yl]carbamate

Solvents

ethyl acetate

methylene chloride

Conditions

Workup

1. 1
   ConcentrationThe reaction solution was concentrated under reduced pressure
2. 2
   workup.ADDITIONby adding toluene
3. 3
   workup.DISSOLUTIONdissolved in methylene chloride (100 ml)
4. 4
   workup.ADDITIONby adding diisopropylethylamine (2.1 g)
5. 5
   workup.ADDITIONthe solution was added dropwise at 0° C
6. 6
   workup.ADDITIONthe dropwise addition
7. 7
   workup.STIRRINGthe mixture was stirred at 0° C. to room temperature overnight
8. 8
   WashThe reaction solution was washed with water and aqueous sodium bicarbonate
9. 9
   Concentrationconcentrated under reduced pressure
10. 10
    workup.ADDITIONby adding toluene

Procedure

Methanol (10 ml), ethyl acetate (10 ml) and a 4 N hydrochloric acid/ethyl acetate solution (30 mL) were added to tert-butyl cis(±)-4-{[(benzyloxy)carbonyl]amino}-3-methoxypiperidine-1-carboxylate obtained in Example (40a) (1.88 g, 5.16 mmol), and the mixture was stirred at room temperature overnight. The reaction solution was concentrated under reduced pressure, azeotropically dehydrated by adding toluene, and dissolved in methylene chloride (100 ml), followed by adding diisopropylethylamine (2.1 g). Chloroacetyl chloride (640 mg, 5.68 mmol) was dissolved in methylene chloride (50 ml), and the solution was added dropwise at 0° C. Following the dropwise addition, the mixture was stirred at 0° C. to room temperature overnight. The reaction solution was washed with water and aqueous sodium bicarbonate, concentrated under reduced pressure, and then azeotropically dehydrated by adding toluene to obtain the title compound. Half of the resulting compound was used for the next reaction without purification.

Source