1,2-Dibromoethane → Ethyl 2,3-dihydrobenzo[b][1,4]dioxine-6-carboxylate

HRID 871267Notes

Reaction equation

HRID 871267 reaction equation
[OH:1][C:2]1[CH:3]=[C:4]([CH:10]=[CH:11][C:12]=1[OH:13])[C:5]([O:7][CH2:8][CH3:9])=[O:6].Br[CH2:15][CH2:16]Br.C([O-])([O-])=O.[K+].[K+]>CN(C=O)C>[O:13]1[CH2:16][CH2:15][O:1][C:2]2[CH:3]=[C:4]([C:5]([O:7][CH2:8][CH3:9])=[O:6])[CH:10]=[CH:11][C:12]1=2

Participants

5

Reactant 3

HCID 78391,2-DibromoethaneHCID 11430Potassium CarbonateHCID 77547Ethyl 3,4-Dihydroxybenzoate

Product 1

HCID 16648286Ethyl 2,3-dihydrobenzo[b][1,4]dioxine-6-carboxylateYield 23%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Conditions

Temperature
70 °C

Procedure

According to the procedure described in Example 6A Step 1, a mixture of ethyl 3,4-dihydroxybenzoate (5.465 g, 30 mmol), 1,2-dibromoethane (5.636 g, 30 mmol), and K2CO3 (6.219 g, 45 mmol) in DMF (100 mL) was heated at 70° C. overnight. The residue was purified by silica gel chromatography with 20-50% EtOAc/hexane as eluants to afford ethyl 2,3-dihydrobenzo[b][1,4]dioxine-6-carboxylate as an oil (1.423 g, 23%). 1H NMR (300 MHz, CDCl3) δ 7.58 (d, 1H), 7.56 (dd, 1H), 6.88 (d, 1H), 4.30 (m, 6H), 1.37 (t, 3H); LC-MS (ESI) m/z 209 (M+H)+.

Workup

  1. customThe residue was purified by silica gel chromatography with 20-50% EtOAc/hexane as eluants

Sources & evidence

ORD record
ord-79c36bb51f974b7c9c2bcc8cc6d5227c
Source dataset
uspto-grants-2015_03
Patent number
US08969587B2

Reaction notes

Loading…