Hydrochloric Acid → Ethyl 2-(4-chloro-1-hydroxy-6-(pyrazin-2-yloxy)-1,3-dihydrobenzo[c][1,2]oxaborol-3-yl)acetate

HRID 1798218Notes

Reaction equation

HRID 1798218 reaction equation
[Cl:1][C:2]1[C:10]2[CH:9]([CH2:11][C:12]([O:14][CH2:15][CH3:16])=[O:13])[O:8][B:7]([OH:17])[C:6]=2[CH:5]=[C:4]([OH:18])[CH:3]=1.C([O-])([O-])=O.[Cs+].[Cs+].Cl[C:26]1[CH:31]=[N:30][CH:29]=[CH:28][N:27]=1.Cl>CN(C=O)C>[Cl:1][C:2]1[C:10]2[CH:9]([CH2:11][C:12]([O:14][CH2:15][CH3:16])=[O:13])[O:8][B:7]([OH:17])[C:6]=2[CH:5]=[C:4]([O:18][C:26]2[CH:31]=[N:30][CH:29]=[CH:28][N:27]=2)[CH:3]=1

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 10796Cesium carbonateHCID 73277ChloropyrazineHCID 58292598Ethyl 2-(4-chloro-1,6-dihydroxy-1,3-dihydrobenzo[c][1,2]oxaborol-3-yl)acetate

Product 1

HCID 58292579Ethyl 2-(4-chloro-1-hydroxy-6-(pyrazin-2-yloxy)-1,3-dihydrobenzo[c][1,2]oxaborol-3-yl)acetateYield 32%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Conditions

Temperature
90 °C

Procedure

To a solution of ethyl 2-(4-chloro-1,6-dihydroxy-1,3-dihydrobenzo[c][1,2]oxaborol-3-yl)acetate (500 mg, 1.85 mmol) in DMF (5 mL) was added Cs2CO3 (1.51 g, 4.62 mmol) at room temperature, followed by 2-chloropyrazine (254 mg, 2.22 mL). The resulting mixture was stirred at 90° C. for 40 min. The mixture was poured into ice-water and acidified to pH=2 with diluted hydrochloric acid. The resulting mixture was extracted with EtOAc (2×25 mL), dried over anhydrous Na2SO4 and concentrated in vacuo. The residue was purified by HPLC to give the product (110 mg, yield: 32%). MS (ESI) m/z=349 [M+H]+.

Workup

  1. extractionThe resulting mixture was extracted with EtOAc (2×25 mL)
  2. dry with materialdried over anhydrous Na2SO4
  3. concentrationconcentrated in vacuo
  4. customThe residue was purified by HPLC

Sources & evidence

ORD record
ord-9f3f65e61f8b4b15a24430f3e2ae8739
Source dataset
uspto-grants-2013_01
Patent number
US08343944B2

Reaction notes

Loading…