2-Chlorobenzoxazole → methyl (2S)-1-(1,3-benzoxazol-2-yl)-2-piperidinecarboxylate

HRID 841935Notes

Reaction equation

HRID 841935 reaction equation
C(N(C(C)C)C(C)C)C.[Cl-].[CH3:11][O:12][C:13]([C@@H:15]1[CH2:20][CH2:19][CH2:18][CH2:17][NH2+:16]1)=[O:14].Cl[C:22]1[O:23][C:24]2[CH:30]=[CH:29][CH:28]=[CH:27][C:25]=2[N:26]=1>C(#N)C>[O:23]1[C:24]2[CH:30]=[CH:29][CH:28]=[CH:27][C:25]=2[N:26]=[C:22]1[N:16]1[CH2:17][CH2:18][CH2:19][CH2:20][C@H:15]1[C:13]([O:12][CH3:11])=[O:14]

Participants

5

Reactant 3

HCID 119862-ChlorobenzoxazoleHCID 81531DiisopropylethylamineHCID 131722236HCID 131722236, compound

Product 1

HCID 10220819methyl (2S)-1-(1,3-benzoxazol-2-yl)-2-piperidinecarboxylate

Reagents, catalysts & solvents 1

HCID 6342AcetonitrileSolvent

Procedure

Ethyldiisopropylamine (6.52 ml) was added to a solution of (2S)-2-(methoxycarbonyl)piperidinium chloride (3.057 g) [see Preparation 1] and 2-chlorobenzoxazole (2.13 ml) in acetonitrile (50 ml). The reaction mixture was stirred at room temperature for 18 hours and then at 50° C. for a further 2 hours. The solvent was removed under reduced pressure and the residue partitioned between ethyl acetate and water, the organic layer was separated, dried over magnesium sulphate and the solvent removed under reduced pressure. The crude product was purified by column chromatography on silica gel eluting with a solvent gradient of 80:10:0, changing to 0:100:0, followed by 0:95:5, by volume, hexane:ethyl acetate:methanol, to afford methyl (2S)-1-(1,3-benzoxazol-2-yl)-2-piperidinecarboxylate (3.18 g) as a solid.

Workup

  1. waitat 50° C. for a further 2 hours
  2. customThe solvent was removed under reduced pressure
  3. customthe residue partitioned between ethyl acetate and water
  4. customthe organic layer was separated
  5. dry with materialdried over magnesium sulphate
  6. customthe solvent removed under reduced pressure
  7. customThe crude product was purified by column chromatography on silica gel eluting with a solvent gradient of 80:10:0

Sources & evidence

ORD record
ord-e61dd39540eb49fdb679353cbaa41570
Source dataset
uspto-grants-2002_04
Patent number
US06372736B1

Reaction notes

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