Hydrochloric Acid → (5-(Benzyloxy)pyridin-3-yl)boronic acid

HRID 1877476

反応式

HRID 1877476 の反応式
Br[C:2]1[CH:3]=[N:4][CH:5]=[C:6]([O:8][CH2:9][C:10]2[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=2)[CH:7]=1.[B:16](OC(C)C)([O:21]C(C)C)[O:17]C(C)C.C([Li])CCC.Cl>C1(C)C=CC=CC=1.O1CCCC1>[CH2:9]([O:8][C:6]1[CH:7]=[C:2]([B:16]([OH:21])[OH:17])[CH:3]=[N:4][CH:5]=1)[C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1

参加物

7

反応物 4

HCID 313Hydrochloric AcidHCID 21531Triisopropyl borateHCID 153891983-(Benzyloxy)-5-bromopyridineHCID 178418339Butyllithium

生成物 1

HCID 53398533(5-(Benzyloxy)pyridin-3-yl)boronic acid

試薬・触媒・溶媒 2

HCID 1140Toluene溶媒HCID 8028Tetrahydrofuran溶媒

反応条件

温度
-70 °C

実験手順

1.91 g of 3-bromo-5-benzyloxypyridine, under argon, are added to a solution of 2 ml of triisopropyl borate in a mixture of 12 ml of toluene and 3 ml of tetrahydrofuran. The solution is cooled to −70° C. and then 5.42 ml of n-butyllithium (1.6N in hexane) are added dropwise. The reaction medium is stirred for 3 hours, and brought back to −20° C., and 7.23 ml of 2N hydrochloric acid are added dropwise. The reaction mixture is left to return to ambient temperature and poured into distilled water. The aqueous phase is extracted with ethyl acetate, and then the organic phase is washed with a saturated solution of sodium chloride, dried over magnesium sulphate and concentrated under reduced pressure, so as to give 0.21 g of [5-(benzyloxy)pyridin-3-yl]boronic acid in the form of a white powder (adapted from Wenjie Li et al. An Improved Protocol for the Preparation of 3-Pyridyl- and Some Arylboronic Acids J. Org. Chem., (2002), 67(15), 5394-5397), the characteristics of which are the following:

後処理

  1. custombrought back to −20° C.
  2. waitThe reaction mixture is left
  3. customto return to ambient temperature
  4. additionpoured
  5. distillationinto distilled water
  6. extractionThe aqueous phase is extracted with ethyl acetate
  7. washthe organic phase is washed with a saturated solution of sodium chloride
  8. dry with materialdried over magnesium sulphate
  9. concentrationconcentrated under reduced pressure

出典と根拠

ORDレコード
ord-d601ff0e341248eba784433b0aeaddd8
出典データセット
uspto-grants-2012_11
特許番号
US08309721B2

関連ノート

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