Chloroform → HCID 131726705, compound

HRID 919012Notes

Reaction equation

HRID 919012 reaction equation
C([O:8][C:9]([C:11]1[CH:29]=[CH:28][C:14]2[O:15][CH2:16][CH:17]([C:19]([CH3:27])([CH3:26])[O:20][SiH2:21][C:22]([CH3:25])([CH3:24])[CH3:23])[O:18][C:13]=2[C:12]=1[CH3:30])=[O:10])C1C=CC=CC=1.[H][H].C(Cl)(Cl)Cl>C(Cl)Cl.[Pd]>[C:22]([SiH2:21][O:20][C:19]([CH3:27])([CH3:26])[CH:17]1[CH2:16][O:15][C:14]2[CH:28]=[CH:29][C:11]([C:9]([OH:10])=[O:8])=[C:12]([CH3:30])[C:13]=2[O:18]1)([CH3:25])([CH3:23])[CH3:24]

Participants

6

Reactant 3

HCID 6212ChloroformHCID 131726706HCID 131726706, compoundHCID 178418361HCID 178418361, compound2×

Product 1

HCID 131726705HCID 131726705, compound

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 6344DichloromethaneSolvent

Procedure

9.63 g or 3-(tert-Butyl-dimethyl-silanyloxymethyl)-5-methyl-2,3-dihydro-benzo[1,4]dioxine-6-carboxylic acid benzyl ester was dissolved in ca. 125 mL of dry CH2Cl2. The solution was transferred to a Parr hydrogenation bottle, and 5 g of 5% Pd on carbon were added. The bottle was charged with hydrogen and shaken on a Parr hydrogenation apparatus for 3 hours; hydrogen uptake ceased after 2 hours, as indicated by pressure monitoring. 100 mL CHCl3 were added, and the Pd/C was filtered off after adding MgSO4 as an aid to increase particle size. The CH2Cl2—CHCl3 phase was washed with 200 mL of 0.1N HCl to remove the by-product benzyl alcohol. The organic layer was dried and evaporated to give 6.47 g 3-(tert-butyl-dimethyl-silanyloxymethyl)-5-methyl-2,3-dihydro-benzo[1,4]dioxine-6-carboxylic acid, alter truce solvent removal in a vacuum oven. TLC Rf=0.35 (1:1 ethyl acetate:hexane). Note: (a) Pd catalyzed hydrogenation is a far superior method to triethylsilane/palladium diacetate for this benzyl ester cleavage, (b) washing product with weak aqueous acid is a good way to remove benzyl alcohol. 1H NMR (300 MHz, CDCl3) δ (ppm): 7.55 (d, 1H), 6.7 (d, 1H), 4.3 (d, 1H), 4.17 (m, 1H), 4.02 (dd, 1H), 3.82 (dd, 1H), 3.75 (dd, 1H), (2.45 (s, 3H), 0.8 (s, 9H), 0.01 (s, 3H).

Workup

  1. additionwere added
  2. filtrationthe Pd/C was filtered off
  3. additionafter adding MgSO4 as an aid
  4. temperatureto increase particle size
  5. washThe CH2Cl2—CHCl3 phase was washed with 200 mL of 0.1N HCl
  6. customto remove the by-product benzyl alcohol
  7. customThe organic layer was dried
  8. customevaporated

Sources & evidence

ORD record
ord-8069dfb39a264e7aab05844fcdf7bf5f
Source dataset
uspto-grants-2016_03
Patent number
US09272986B2

Reaction notes

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