Diethyl Ether → Tert-butyl 4-(2,2-dibromovinyl)piperidine-1-carboxylate

HRID 1635955Notes

Reaction equation

HRID 1635955 reaction equation
[C:1]([Br:5])(Br)(Br)[Br:2].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.[C:25]([O:29][C:30]([N:32]1[CH2:37][CH2:36][CH:35]([CH:38]=O)[CH2:34][CH2:33]1)=[O:31])([CH3:28])([CH3:27])[CH3:26].CCOCC>C(Cl)Cl>[C:25]([O:29][C:30]([N:32]1[CH2:37][CH2:36][CH:35]([CH:38]=[C:1]([Br:5])[Br:2])[CH2:34][CH2:33]1)=[O:31])([CH3:28])([CH3:26])[CH3:27]

Participants

6

Reactant 4

HCID 3283Diethyl EtherHCID 11205Carbon tetrabromideHCID 11776TriphenylphosphineHCID 1514430tert-Butyl 4-formylpiperidine-1-carboxylate

Product 1

HCID 11474132Tert-butyl 4-(2,2-dibromovinyl)piperidine-1-carboxylate

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent3×

Procedure

A solution of 48.615 g (146.6 mmole) carbon tetrabromide in 150 mL DCM was added dropwise with stirring to a solution of 76.895 g (293.2 mmole) triphenylphosphine in 150 mL DCM in a 1-L rb flask with ice bath cooling over 1.75 hours. After 40 minutes, a solution of 15.631 g (73.29 mmole) 1-(t-butoxycarbonyl)-4-formyl-piperidine (from Step 2 above) in 100 mL DCM was added to the resulting brown suspension with stirring and cooling over 40 minutes. After one hour, 200 mL ether and 400 mL hexanes was added. The top suspension was filtered through Celite, and the residue was resuspended in 150 mL DCM and treated with 300 mL ether. The mixture was filtered, and the solid was washed with hexanes till total filtrate was 2 L. The filtrate was filtered again through Celite and washed with hexanes. The filtrate was washed with 100 mL 5 % NaHCO3, 300 mL water (2×), and 150 mL brine. The organic layer was dried over Na2SO4 and concentrated under vacuum to give crude product as a yellowish solid. Flash chromatography (FC) on 250 g silica gel (0˜15% EtOAc in hexanes) gave title compound as a white solid. RF: 0.57 (15% EtOAc in hexanes); 1H NMR (500 MHz) δ 6.25 (d, J=8.9 Hz, 1H), 4.04˜4.12 (m, 2H), 2.75˜2.83 (m, 2H), 2.42˜2.50 (m, 1H), 1.69˜1.75 (m, 2H), 1.47 (s, 9H), 1.29˜1.37 (m, 2H).

Workup

  1. temperaturecooling over 1.75 hours
  2. temperaturecooling over 40 minutes
  3. waitAfter one hour
  4. filtrationThe top suspension was filtered through Celite
  5. additiontreated with 300 mL ether
  6. filtrationThe mixture was filtered
  7. washthe solid was washed with hexanes till total filtrate
  8. filtrationThe filtrate was filtered again through Celite
  9. washwashed with hexanes
  10. washThe filtrate was washed with 100 mL 5 % NaHCO3, 300 mL water (2×), and 150 mL brine
  11. dry with materialThe organic layer was dried over Na2SO4
  12. concentrationconcentrated under vacuum
  13. customto give crude product as a yellowish solid

Sources & evidence

ORD record
ord-dac8d06f08ee43dc8f36aaf783b4cbc2
Source dataset
uspto-grants-2003_01
Patent number
US06511994B2

Reaction notes

Loading…