Sulfuric Acid → (4-Methoxyphenyl)boronic acid

HRID 1595684Notes

Reaction equation

HRID 1595684 reaction equation
Br[C:2]1[CH:7]=[CH:6][C:5]([O:8][CH3:9])=[CH:4][CH:3]=1.[Mg].C([O:13][B:14](OCC)[O:15]CC)C.S(=O)(=O)(O)O>C(OCC)C.O>[CH3:9][O:8][C:5]1[CH:6]=[CH:7][C:2]([B:14]([OH:15])[OH:13])=[CH:3][CH:4]=1

Participants

7

Reactant 4

HCID 1118Sulfuric AcidHCID 77304-BromoanisoleHCID 9009Triethyl borateHCID 5462224Magnesium

Product 1

HCID 201262(4-Methoxyphenyl)boronic acid

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 3283Diethyl EtherSolvent3×

Conditions

Temperature
-70 °C

Procedure

100 ml of a solution of 10 g of p-bromoanisole in anhydrous diethyl ether is added dropwise under reflux to a suspension, under inert gas, of 1.3 g of magnesium turnings in 5 ml of anhydrous diethyl ether, and the mixture is left under reflux for 2 hours. The reaction medium is then poured into a solution of 9.02 ml of triethylborate in 60 ml of anhydrous ether cooled down to −70° C. After agitation for 1 hour at −70° C., then for 1 hour at ambient temperature, the solution is poured into a mixture comprising 11 ml of sulphuric acid and 50 g of ice and water followed by agitation for 1 hour. The organic phase is extracted with 100 ml of an aqueous solution saturated in sodium bicarbonate, the aqueous phases are combined, then reacidified with 6N hydrochloric acid, extracted with ether, dried and evaporated under reduced pressure. 3.9 g of expected product is obtained.

Workup

  1. waitthe mixture is left
  2. temperatureunder reflux for 2 hours
  3. waitfor 1 hour at ambient temperature
  4. waitfollowed by agitation for 1 hour
  5. extractionThe organic phase is extracted with 100 ml of an aqueous solution saturated in sodium bicarbonate
  6. extractionextracted with ether
  7. customdried
  8. customevaporated under reduced pressure

Sources & evidence

ORD record
ord-5fb6ef49cdf7468687cee5c073e86602
Source dataset
uspto-grants-2001_09
Patent number
US06288126B1

Reaction notes

Loading…