Lithium Hexamethyldisilazide → Methyl 4-[2-(2-benzyloxy-3-pyridyl)ethenyl]benzoate

HRID 2395063Notes

Reaction equation

HRID 2395063 reaction equation
[Br-].[CH3:2][O:3][C:4]([C:6]1[CH:31]=[CH:30][C:9]([CH2:10][P+](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=[CH:8][CH:7]=1)=[O:5].C[Si]([N-][Si](C)(C)C)(C)C.[Li+].[CH2:42]([O:49][C:50]1[C:55]([CH:56]=O)=[CH:54][CH:53]=[CH:52][N:51]=1)[C:43]1[CH:48]=[CH:47][CH:46]=[CH:45][CH:44]=1>C1COCC1>[CH2:42]([O:49][C:50]1[C:55]([CH:56]=[CH:10][C:9]2[CH:8]=[CH:7][C:6]([C:4]([O:3][CH3:2])=[O:5])=[CH:31][CH:30]=2)=[CH:54][CH:53]=[CH:52][N:51]=1)[C:43]1[CH:44]=[CH:45][CH:46]=[CH:47][CH:48]=1

Participants

5

Reactant 3

HCID 2733832Lithium HexamethyldisilazideHCID 2764257[4-(Methoxycarbonyl)benzyl](triphenyl)phosphonium bromideHCID 189739592-Benzyloxy-3-pyridinecarbaldehyde

Product 1

HCID 53806701Methyl 4-[2-(2-benzyloxy-3-pyridyl)ethenyl]benzoateYield 79%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

(4-Methoxycarbonylbenzyl)triphenylphosphonium bromide (16.6 g, 33.8 mmol) was suspended in THF (70 ml) under Argon. Lithium bis(trimethylsilyl)amide (1M in THF, 40.5 ml) was added. The reaction mixture was stirred for 1 hour at ambient temperature; the colour changed to orange. 2-Benzyloxy-3-pyridinecarbaldehyde (7.2 g, 33.8 mmol) was added as a solution in THF (50 ml) and the reaction mixture was stirred at amibent temperature overnight (shielded from light). The reaction mixture was partitioned between EtOAc/water, the organic phase was dried (MgSO4) and evaporated. Purification by chromatography (SiO2, eluting with CH2Cl2 /hexane) gave methyl 4-[2-(2-benzyloxy-3-pyridyl)ethenyl]benzoate (9.2 g, 79%).

Workup

  1. stirringthe reaction mixture was stirred at amibent temperature overnight (shielded from light)
  2. customThe reaction mixture was partitioned between EtOAc/water
  3. dry with materialthe organic phase was dried (MgSO4)
  4. customevaporated
  5. customPurification
  6. washby chromatography (SiO2, eluting with CH2Cl2 /hexane)

Sources & evidence

ORD record
ord-4597395479584bf9a050adec982d963b
Source dataset
uspto-grants-1998_09
Patent number
US05811459

Reaction notes

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