Borane → HCID 68434406, compound

HRID 1867362Notes

Reaction equation

HRID 1867362 reaction equation
[O:1]1[CH:5]=[CH:4][N:3]=[CH:2]1.B.[Li]CCCC.[C:12]([N:19]1[CH2:24][CH2:23][CH2:22][CH2:21][C:20]1=O)([O:14][C:15]([CH3:18])([CH3:17])[CH3:16])=[O:13].C1C[O:29]CC1>>[C:15]([O:14][C:12]([N:19]1[CH2:24][CH2:23][C:22]([OH:29])([C:2]2[O:1][CH:5]=[CH:4][N:3]=2)[CH2:21][CH2:20]1)=[O:13])([CH3:18])([CH3:17])[CH3:16]

Participants

6

Reactant 5

HCID 6331BoraneHCID 8028Tetrahydrofuran3×HCID 9255OxazoleHCID 7577838tert-Butyl 2-oxopiperidine-1-carboxylateHCID 178418339Butyllithium

Product 1

HCID 68434406HCID 68434406, compoundYield 44%

Conditions

Temperature
-78 °C

Procedure

To a solution of oxazole (1 g, 14 mmol) in anhydrous THF (10 ml) was added borane. THF complex (14 ml, 1M in THF, 14 mmol) and the mixture stirred for 1 h, after which time the reaction was cooled to −78° C. and nBuLi (9 ml, 1.6 M in hexanes, 14 mmol) added dropwise and the reaction stirred for a further 1 h. A solution of Boc-piperidone (3.2g, 16 mmol) in THF (10 ml) is then added, the reaction stirred for a further 4 h at −78° C. before allowing the reaction to reach room temperature overnight. The solvent is then evaporated, the residue redissolved in EtOAc, washed with saturated ammonium chloride solution, dried (Na2SO4) and concentrated. Purification by flash column chromatography (EtOAc:Heptane 3:7) affords the title product (1.9 g, 44%) as a colourless gum, contaminated with an unknown byproduct. MS: 269.2 (MH+)

Workup

  1. stirringthe reaction stirred for a further 4 h at −78° C.
  2. customthe reaction
  3. waitto reach room temperature overnight
  4. customThe solvent is then evaporated
  5. dissolutionthe residue redissolved in EtOAc
  6. washwashed with saturated ammonium chloride solution
  7. dry with materialdried (Na2SO4)
  8. concentrationconcentrated
  9. customPurification by flash column chromatography (EtOAc:Heptane 3:7)

Sources & evidence

ORD record
ord-b2c0527240fd4e4c9b64c88dd5e968e8
Source dataset
uspto-grants-2009_12
Patent number
US07632829B2

Reaction notes

Loading…