tert-Butyldimethylsilyl chloride → (+/-)-(2S,3R)-1-tert-Butoxycarbonyl-3-(tert-butyldimethylsilanyloxy)pipecolic acid methyl ester

HRID 501644ノート

反応式

HRID 501644 の反応式
[CH3:1][O:2][C:3](=[O:18])[C@@H:4]1[C@H:9]([OH:10])[CH2:8][CH2:7][CH2:6][N:5]1[C:11]([O:13][C:14]([CH3:17])([CH3:16])[CH3:15])=[O:12].CCN(C(C)C)C(C)C.[Si:28](Cl)([C:31]([CH3:34])([CH3:33])[CH3:32])([CH3:30])[CH3:29]>C(Cl)Cl.CN(C1C=CN=CC=1)C>[CH3:1][O:2][C:3](=[O:18])[C@@H:4]1[C@H:9]([O:10][Si:28]([C:31]([CH3:34])([CH3:33])[CH3:32])([CH3:30])[CH3:29])[CH2:8][CH2:7][CH2:6][N:5]1[C:11]([O:13][C:14]([CH3:15])([CH3:17])[CH3:16])=[O:12]

参加物

6

反応物 3

HCID 28928tert-Butyldimethylsilyl chloride2 回HCID 81531Diisopropylethylamine2 回HCID 59754228rac-1-tert-butyl 2-methyl (2R,3S)-3-hydroxypiperidine-1,2-dicarboxylate

生成物 1

HCID 68458695(+/-)-(2S,3R)-1-tert-Butoxycarbonyl-3-(tert-butyldimethylsilanyloxy)pipecolic acid methyl ester収率 81%

試薬・触媒・溶媒 2

HCID 142844-(Dimethylamino)pyridine触媒HCID 6344Dichloromethane溶媒

実験手順

To a solution of 77C (3.3 g, 12.7 mmol) in DCM (50 mL) was added DIPEA (6.63 mL, 38.1 mmol), tert-butyldimethylsilyl chloride (3.83 g, 25.4 mmol, 2.0 equiv) and DMAP (310 mg, 5.24 mmol, 0.2 equiv). The resulting mixture was stirred at rt overnight. TLC showed no completion and therefore another 2.2 mL of DIPEA and 1.91 g of tert-butyldimethylsilyl chloride were added and stirred at rt for 3 days. The mixture was concentrated and the residue was diluted with EtOAc (100 mL), washed with 0.5 N HCl (2×30 mL), brine (2×30 mL), dried (MgSO4) and evaporated to give the crude product as a light pink oil. Purification of the crude product by flash chromatography (5-10% EtOAc/hexane) gave the desired product 77D (3.8 g, 81%): Rf (10% EtOAc/hexane) 0.25; HPLC (Phenomenex Luna 5 u C18 4.6×50 mm, linear gradient over 4 min) retention time 4.3 min (100%); MS (ES) m/z 374 [M+1]+.

後処理

  1. stirringstirred at rt for 3 days
  2. concentrationThe mixture was concentrated
  3. additionthe residue was diluted with EtOAc (100 mL)
  4. washwashed with 0.5 N HCl (2×30 mL), brine (2×30 mL)
  5. dry with materialdried (MgSO4)
  6. customevaporated
  7. customto give the crude product as a light pink oil
  8. customPurification of the crude product by flash chromatography (5-10% EtOAc/hexane)

出典と根拠

ORDレコード
ord-784f3971174b4cb0a2f23fbac050c4d8
出典データセット
uspto-grants-2010_08
特許番号
US07772267B2

反応ノート

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