Allyl bromide → 4-[10,11-dihydro-5-(2-propenyl)-5H-dibenzo[a,d]cyclohepten-5-yl]-1-methyl-1,2,5,6-tetrahydropyridine

HRID 128636

Reaction equation

HRID 128636 reaction equation
[CH:1]1[C:11]2[CH2:10][CH2:9][C:8]3[CH:12]=[CH:13][CH:14]=[CH:15][C:7]=3[C:6](=[C:16]3[CH2:21][CH2:20][N:19]([CH3:22])[CH2:18][CH2:17]3)[C:5]=2[CH:4]=[CH:3][CH:2]=1.[CH2:23]([Li])[CH2:24][CH2:25]C.C(Br)C=C>C1COCC1>[CH2:25]([C:6]1([C:16]2[CH2:17][CH2:18][N:19]([CH3:22])[CH2:20][CH:21]=2)[C:7]2[CH:15]=[CH:14][CH:13]=[CH:12][C:8]=2[CH2:9][CH2:10][C:11]2[CH:1]=[CH:2][CH:3]=[CH:4][C:5]1=2)[CH:24]=[CH2:23]

Participants

5

Reactant 3

HCID 7841Allyl bromideHCID 1688974-(10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-ylidene)-1-methylpiperidineHCID 178418339Butyllithium

Product 1

HCID 97975634-[10,11-dihydro-5-(2-propenyl)-5H-dibenzo[a,d]cyclohepten-5-yl]-1-methyl-1,2,5,6-tetrahydropyridineYield 70.2%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Conditions

Temperature
-78 °C

Procedure

Dissolved 4-(10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-ylidene)-1-methylpiperidine (10 g, 34.6 mmol) in 200 mL of dry THF, and cooled to -78° C. under a nitrogen atmosphere. Added n-butyl lithium (15.2 mL of 2.5M in hexane, 38.0 mmol) dropwise via syringe. Warmed to 0° C, and stirred for 60 mins. Recooled to -78° C, and added allyl bromide (4.6 g, 3.3 mL, 38.0 mmol) dropwise via syringe. Warmed to room temperature slowly, and stirred for 5 hours. Added saturated NH4Cl, and extracted with ether. Dried the combined organic extracts with MgSO4, filtered, and evaporated. Purified the crude product by flash chromatography on silica gel eluting with 5:95:0.1MeOH:EtOAc:NH4OH. Combined appropriate fractions, and evaporated to give 8.0 g (70% yield) of 4-[10,11-dihydro-5-(2-propenyl)-5H-dibenzo[a,d]cyclohepten-5-yl]-1-methyl-1,2,5,6-tetrahydropyridine as an oil. Dissolved free base in ether, and added 19 weight % HCl-EtOH until acidic. Added additional ether, and let stand to precipitate hydrochloride salt. Recrystallized salt from acetonitrile-ether.

Workup

  1. temperatureWarmed to 0° C
  2. customRecooled to -78° C
  3. temperatureWarmed to room temperature slowly
  4. stirringstirred for 5 hours
  5. extractionAdded saturated NH4Cl, and extracted with ether
  6. dry with materialDried the combined organic extracts with MgSO4
  7. filtrationfiltered
  8. customevaporated
  9. customPurified the crude product by flash chromatography on silica gel eluting with 5:95:0.1MeOH
  10. customevaporated

Sources & evidence

ORD record
ord-b8b318ee6be64d839f225e10ae65e2a6
Source dataset
uspto-grants-1995_11
Patent number
US05464840

Linked notes

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