Benzyl Bromide → 5-Methyl-1',2',3',6'-tetrahydro-2,4'-bipyridine

HRID 41506Notes

Reaction equation

HRID 41506 reaction equation
C(Br)C1C=CC=CC=1.[CH3:9][C:10]1[CH:11]=[CH:12][C:13]([C:16]2[CH:21]=[CH:20][N:19]=[CH:18][CH:17]=2)=[N:14][CH:15]=1.C(N(CC)CC)C.[H][H]>C(O)(C)C>[CH3:9][C:10]1[CH:11]=[CH:12][C:13]([C:16]2[CH2:21][CH2:20][NH:19][CH2:18][CH:17]=2)=[N:14][CH:15]=1

Participants

6

Reactant 4

HCID 7498Benzyl BromideHCID 8471TriethylamineHCID 112867135-Methyl-2,4'-bipyridineHCID 178418361HCID 178418361, compound

Product 1

HCID 114920195-Methyl-1',2',3',6'-tetrahydro-2,4'-bipyridineYield 40.1%

Reagents, catalysts & solvents 1

HCID 3776IsopropanolSolvent

Conditions

Temperature
50 °C

Procedure

Benzyl bromide in an amount of 10.5 g was added to a solution of 10 g of 5-methyl-2,4′-bipyridine in 70 mL of isopropyl alcohol, and stirred for 5 hours at 50° C. To the resulting reaction solution, 1.0 g of 2% palladium-S carbon and 6.0 g of triethylamine were added. This admixture was put in an autoclave, the autoclave's atmosphere was replaced twice with nitrogen gas under a nitrogen pressure of 196 kPa, and then hydrogen gas was blown into the autoclave over 3 hours at 80° C. under a hydrogen pressure of 196 kPa until the absorption of hydrogen gas in a volume of 4,200 mL was completed. After the replacement with nitrogen, the catalyst was filtered out and the resulting filtrate was concentrated under a reduced pressure of 1.33 kPa until the quantity thereof was reduced to 18.0 g. Further thereto, 50 mL of water and 10 g of a 25% aqueous solution of sodium hydroxide were added. The resulting solution was extracted with three 200 mL portions of ethyl acetate, and the organic layer was concentrated. The thus obtained solid was adsorbed to NH2-modified silica gel (produced by Biotage Japan, Ltd.), and eluted with ethyl acetate. The fraction obtained was concentrated, and the crystals thus deposited were dried to give 4.1 g of the intended compound as light yellow crystals. Yield rate: 40%, EI-MS: (m/z) 174 (M+), melting point: 78-80° C.

Workup

  1. additionwere added
  2. custompressure of 196 kPa until the absorption of hydrogen gas in a volume of 4,200 mL
  3. filtrationAfter the replacement with nitrogen, the catalyst was filtered out
  4. concentrationthe resulting filtrate was concentrated under a reduced pressure of 1.33 kPa until the quantity
  5. additionFurther thereto, 50 mL of water and 10 g of a 25% aqueous solution of sodium hydroxide were added
  6. extractionThe resulting solution was extracted with three 200 mL portions of ethyl acetate
  7. concentrationthe organic layer was concentrated
  8. washeluted with ethyl acetate
  9. customThe fraction obtained
  10. concentrationwas concentrated
  11. customthe crystals thus deposited were dried

Sources & evidence

ORD record
ord-77ec786a1977460da5872cdb1e2b3962
Source dataset
uspto-grants-2013_09
Patent number
US08530662B2

Reaction notes

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