Hydrochloric Acid → 3-Tert-butyl-4-methoxyphenylboronic acid

HRID 1057955Notes

Reaction equation

HRID 1057955 reaction equation
[C:1]([C:5]1[CH:6]=[C:7](Br)[CH:8]=[CH:9][C:10]=1[O:11][CH3:12])([CH3:4])([CH3:3])[CH3:2].C([Li])CCC.[B:19](OC)([O:22]C)[O:20]C.Cl>C1COCC1>[C:1]([C:5]1[CH:6]=[C:7]([B:19]([OH:22])[OH:20])[CH:8]=[CH:9][C:10]=1[O:11][CH3:12])([CH3:4])([CH3:3])[CH3:2]

Participants

6

Procedure

4 g (16.5 mmol) of 3-tert-butyl-4-methoxybromobenzene and 50 ml of THF are introduced into a three-necked flask under a stream of nitrogen. 7.9 ml (19.8 mmol) of n-butyllithium (2.5 M in hexane) are added dropwise at −78° C., the mixture is stirred for 15 minutes at this temperature, 5.6 ml (49.5 mmol) of trimethyl borate are added and the mixture is stirred for 2 hours. 20 ml of hydrochloric acid (1 N) are added at −50° C. and the mixture is allowed to return to room temperature. The reaction medium is extracted with ethyl ether and the organic phase is separated out after settling has taken place, dried over magnesium sulphate and evaporated. 3.79 g (100%) of the expected boronic acid are collected, which is used in its present state for the rest of the synthesis.

Workup

  1. additionare added
  2. customto return to room temperature
  3. extractionThe reaction medium is extracted with ethyl ether
  4. customthe organic phase is separated out after settling
  5. dry with materialdried over magnesium sulphate
  6. customevaporated
  7. custom3.79 g (100%) of the expected boronic acid are collected
  8. customwhich is used in its present state for the rest of the synthesis

Sources & evidence

ORD record
ord-a7b1f47541cd4ec0b6bf8a8b72ec2320
Source dataset
uspto-grants-2003_02
Patent number
US06515021B1

Reaction notes

Loading…