Acetyl chloride → 6-Acetyl-5,6,7,8-tetrahydro-1,6-naphthyridine

HRID 480564Notes

Reaction equation

HRID 480564 reaction equation
[N:1]1[C:10]2[CH2:9][CH2:8][NH:7][CH2:6][C:5]=2[CH:4]=[CH:3][CH:2]=1.C(N(CC)CC)C.[C:18](Cl)(=[O:20])[CH3:19]>C(Cl)Cl>[C:18]([N:7]1[CH2:8][CH2:9][C:10]2[N:1]=[CH:2][CH:3]=[CH:4][C:5]=2[CH2:6]1)(=[O:20])[CH3:19]

Participants

5

Reactant 3

HCID 6367Acetyl chlorideHCID 8471TriethylamineHCID 131938825,6,7,8-Tetrahydro-1,6-naphthyridine

Product 1

HCID 187651916-Acetyl-5,6,7,8-tetrahydro-1,6-naphthyridineYield 58%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

To a solution of 5,6,7,8-tetrahydro-1,6-naphthyridine (4.9 g, 36.5 mmol) in CH2Cl2 at 0° C. was added triethylamine (6.1 ml, 43.8 mmol) and acetyl chloride (3.11 ml, 43.8 mmol) dropwise and the reaction was allowed to warm to room temperature and stirred for a further 18 h. The reaction mixture was partitioned between H2O and CH2Cl2, the layers were separated and the aqueous layer was extracted twice more with CH2Cl2. The combined organic layers were dried over MgSO4 and evaporated under reduced pressure to afford a residue which was purified on silica gel, eluting with EtOAc/MeOH/0.88NH3 (95/5/1, v/v). This afforded the subtitle compound (58%) as an oil. Rf 0.60 (CH2Cl2/MeOH/0.88NH3 84/14/2, v/v). 1H NMR (CDCl3) δ: 2.15 (3H, s), 3.04 (2H, m), 3.75 and 3.90 (2H,2×m), 4.60 and 4.70 (2H,2×s), 7.10 (1H, m), 7.42 (1H,m), 8.42 (1H, m).

Workup

  1. customThe reaction mixture was partitioned between H2O and CH2Cl2
  2. customthe layers were separated
  3. extractionthe aqueous layer was extracted twice more with CH2Cl2
  4. dry with materialThe combined organic layers were dried over MgSO4
  5. customevaporated under reduced pressure
  6. customto afford a residue which
  7. customwas purified on silica gel
  8. washeluting with EtOAc/MeOH/0.88NH3 (95/5/1

Sources & evidence

ORD record
ord-d02463d38a8c4f53a98a602183f134bb
Source dataset
uspto-grants-2003_11
Patent number
US06653302B2

Reaction notes

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