(2-Methylpropyl)boronic acid → 4,4,5,5-Tetramethyl-2-(2-methylpropyl)-1,3,2-dioxaborolane

HRID 485637ノート

反応式

HRID 485637 の反応式
[CH3:1][CH:2]([CH3:7])[CH2:3][B:4]([OH:6])[OH:5].O.O.O.O.O.O.O[C:15]([C:18](O)([CH3:20])[CH3:19])([CH3:17])[CH3:16]>CCOCC.CCCCCC>[CH3:16][C:15]1([CH3:17])[C:18]([CH3:20])([CH3:19])[O:6][B:4]([CH2:3][CH:2]([CH3:7])[CH3:1])[O:5]1

参加物

5

反応物 2

HCID 2734395(2-Methylpropyl)boronic acidHCID 20268938Pinacol hexahydrate

生成物 1

HCID 134912534,4,5,5-Tetramethyl-2-(2-methylpropyl)-1,3,2-dioxaborolane収率 48.4%

試薬・触媒・溶媒 2

HCID 3283Diethyl Ether溶媒HCID 8058Hexane溶媒

実験手順

A solution of 50.13 g (0.494 mol) of 2-methylpropylboronic acid in 300 mL of ether, prepared by a procedure substantially similar to the foregoing, was contacted with 112.63 g (0.494 mol) of pinacol hexahydrate and stirred for 24 hours. At the end of this period, the resulting reaction mixture was diluted with 500 mL of hexane. A top layer formed which was separated from the rest of the mixture and contacted with 18 mL of water. After stirring for 15 minutes, 9.52 g of a solid separated, which was removed by filtration. The remaining hexane layer was dried over Na2SO4 and residual solvent was removed by evaporation. The remaining material was then distilled using a 6" spinning band distillation column, to obtain 43.98 g (0.239 mol, 48.4%) of an oil, bp: 65°-72°/13 mm, 1H NMR (90 MHz, CDCl3): δ0.65 (d, J=6.6 Hz, 2), 0.93 (d, J=6.6 Hz, 6), 1.25 (s, 12), 1.86 (hep, J=6.6 Hz, 1); Anal. Calcd. for C10H21O2B: C, 65.25; H, 11.50; B, 5.87; Found: C, 65.07, H, 11.52; B, 6.01.

後処理

  1. customAt the end of this period, the resulting reaction mixture
  2. customA top layer formed which
  3. customwas separated from the rest of the mixture
  4. stirringAfter stirring for 15 minutes
  5. custom9.52 g of a solid separated
  6. customwhich was removed by filtration
  7. dry with materialThe remaining hexane layer was dried over Na2SO4 and residual solvent
  8. customwas removed by evaporation
  9. distillationThe remaining material was then distilled
  10. distillationband distillation column

出典と根拠

ORDレコード
ord-a512926db46e401dbbce52be89191238
出典データセット
uspto-grants-1985_08
特許番号
US04537773

反応ノート

読み込み中…