Tributylphosphine → (E)-3-(2,3-dihydro-benzo[1,4]dioxin-2-ylmethoxy)-but-2-enoic acid ethyl ester

HRID 18992

Reaction equation

HRID 18992 reaction equation
[O:1]1[C:6]2[CH:7]=[CH:8][CH:9]=[CH:10][C:5]=2[O:4][CH2:3][CH:2]1[CH2:11][OH:12].[CH2:13]([O:15][C:16](=[O:20])[C:17]#[C:18][CH3:19])[CH3:14].C(P(CCCC)CCCC)CCC>O1CCCC1>[CH2:13]([O:15][C:16](=[O:20])/[CH:17]=[C:18](/[O:12][CH2:11][CH:2]1[O:1][C:6]2[CH:7]=[CH:8][CH:9]=[CH:10][C:5]=2[O:4][CH2:3]1)\[CH3:19])[CH3:14]

Participants

5

Reactant 3

HCID 13831TributylphosphineHCID 193141,4-Benzodioxane-2-methanolHCID 78043Ethyl 2-butynoate

Product 1

HCID 66899651(E)-3-(2,3-dihydro-benzo[1,4]dioxin-2-ylmethoxy)-but-2-enoic acid ethyl esterYield 40.2%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

To a stirred mixture of (2,3-dihydro-benzo[1,4]dioxin-2-yl)-methanol (1.01 g, 5.90 mmol) and ethyl-2-butynoate (820 mg, 7.08 mmol) in tetrahydrofuran (15 mL) was added tri-n-butylphosphine (0.25 g, 1.18 mmol). The mixture was stirred at room temperature for 1.5 h. Upon completion of the reaction the tetrahydrofuran was removed in vacuo. The crude product obtained was purified by ISCO flash chromatography (Teledyne Isco RediSep Flash Column 40 g; 0% to 50% ethyl acetate/hexanes) to afford (E)-3-(2,3-dihydro-benzo[1,4]dioxin-2-ylmethoxy)-but-2-enoic acid ethyl ester (660 mg, 40%) as a colorless oil: LR-ES-MS m/z calculated for C15H18O5 [M]+ 278, observed [M+H]+ 279.

Workup

  1. customwas removed in vacuo
  2. customThe crude product obtained
  3. customwas purified by ISCO flash chromatography (Teledyne Isco RediSep Flash Column 40 g; 0% to 50% ethyl acetate/hexanes)

Sources & evidence

ORD record
ord-424f5c5691384160a9ed055e17cf6b2b
Source dataset
uspto-grants-2010_06
Patent number
US07741327B2

Linked notes

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