Tributylvinyltin → 3-Methyl-4-vinylbenzofuran-2-carboxylic acid ethyl ester

HRID 29320

Reaction equation

[CH2:1]([O:3][C:4]([C:6]1[O:7][C:8]2[CH:15]=[CH:14][CH:13]=[C:12](OS(C(F)(F)F)(=O)=O)[C:9]=2[C:10]=1[CH3:11])=[O:5])[CH3:2].[CH:24]([Sn](CCCC)(CCCC)CCCC)=[CH2:25].[Cl-].[Li+]>CN(C=O)C.O.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[CH2:1]([O:3][C:4]([C:6]1[O:7][C:8]2[CH:15]=[CH:14][CH:13]=[C:12]([CH:24]=[CH2:25])[C:9]=2[C:10]=1[CH3:11])=[O:5])[CH3:2]

Participants

Conditions

Temperature: 90 °C

Procedure

To a solution of 2.48 g (7.05 mmol) of 3-methyl-4-trifluoromethanesulfonyloxy-benzofuran-2-carboxylic acid ethyl ester (Example 20, Step 2) in 30 mL of DMF was added 2.16 mL (7.40 mmol) of vinyl tributyltin, 0.898 g (21.1 mmol) of lithium chloride and 0.247 g (0.352 mmol) of tetrakis(triphenylphosphine)palladium(0). The reaction was heated to 90° C. for 3 h and then cooled to room temperature. The reaction was diluted with water and extracted with ether. The combined organics were washed with water and brine, dried over magnesium sulfate, filtered and concentrated in vacuo. The residue was chromatographed on silica gel eluting with ethyl acetate/hexanes (1:25) to provide 1.22 g of 3-methyl-4-vinylbenzofuran-2-carboxylic acid ethyl ester.

Workup

temperaturecooled to room temperature
extractionextracted with ether
washThe combined organics were washed with water and brine
dry with materialdried over magnesium sulfate
filtrationfiltered
concentrationconcentrated in vacuo
customThe residue was chromatographed on silica gel eluting with ethyl acetate/hexanes (1:25)

Sources & evidence

ORD record: ord-b0c9cf25ebb547d1903fb5e5bb5ef8a5
Source dataset: uspto-grants-2008_09
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US07420001B2

Linked notes

Loading…