1-Methoxy-3-trimethylsilyloxy-1,3-butadiene → 3,4,5,6-Tetrahydrobenzo[c]quinolizin-3-(4aH)-one

HRID 380452

Reaction equation

HRID 380452 reaction equation
C[C:2]1[C:3](=[O:17])[CH2:4][CH2:5][N:6]2[C:11]=1[CH2:10][CH2:9][C:8]1[CH:12]=[C:13](C)[CH:14]=[CH:15][C:7]2=1.COC=CC(O[Si](C)(C)C)=C.C([O-])(O)=O.[Na+]>C(Cl)Cl.Cl[Ti](Cl)(Cl)Cl>[CH:5]1[N:6]2[CH:11]([CH2:2][C:3](=[O:17])[CH:4]=1)[CH2:10][CH2:9][C:8]1[CH:12]=[CH:13][CH:14]=[CH:15][C:7]2=1

Participants

6

Reactant 3

HCID 1010511-Methoxy-3-trimethylsilyloxy-1,3-butadiene2×HCID 516892Sodium BicarbonateHCID 10220187AS-601811

Product 1

HCID 104427523,4,5,6-Tetrahydrobenzo[c]quinolizin-3-(4aH)-oneYield 25.1%

Reagents, catalysts & solvents 2

HCID 24193Titanium TetrachlorideCatalystHCID 6344DichloromethaneSolvent2×

Procedure

To a stirred solution of compound 4 [(QW)n=H, R3=R4=H] (4 g, 14.42 mmol) of the example 3, in 75 ml of anhydrous CH2Cl2 under argon at −10° C. is added, dropwise in 7 min, 28.84 ml of a 1M solution of TiCl4 in CH2Cl2 maintaining the temperature below −5° C. Then 1-methoxy-3-(trimethylsilyloxy)-1-3-butadiene (compound 6, R1=MeO, R2=H, R6=H) (3.29 ml, 17.3 mmol) is added by syringe at 0° C., and the reaction was left aside at room temperature for 1 h. The reaction mixture is added, cautiously, with 100 ml of NaHCO3 satured solution, and then stirred for 30 min. The organic layer is separated, washed with water, filtered on Celite and dried over Na2SO4. After removal of the solvent the crude product is purified by flash column chromatography (eluant light-petroleum ether/ethyl acetate 1:4) affording 0.72 g (25% yield) of the expected product (white crystals, m.p.: 135-137° C.).

Workup

  1. customthe temperature below −5° C
  2. additionThe reaction mixture is added
  3. customThe organic layer is separated
  4. washwashed with water
  5. filtrationfiltered on Celite
  6. dry with materialdried over Na2SO4
  7. customAfter removal of the solvent the crude product
  8. customis purified by flash column chromatography (eluant light-petroleum ether/ethyl acetate 1:4)

Sources & evidence

ORD record
ord-33c1855d72ca466e9a3ad6b1d107fe27
Source dataset
uspto-grants-2001_10
Patent number
US06303622B1

Linked notes

Loading…