Imidazole → HCID 19021839, compound

HRID 1109082Notes

Reaction equation

HRID 1109082 reaction equation
[OH:1][C:2]1[C:3]([CH3:21])=[C:4]([CH3:20])[C:5]2[O:10][C:9]([CH3:17])([CH2:11][CH2:12][CH:13]=[C:14]([CH3:16])[CH3:15])[CH2:8][C:7](=[O:18])[C:6]=2[CH:19]=1.[Si:22](Cl)([C:25]([CH3:28])([CH3:27])[CH3:26])([CH3:24])[CH3:23].N1C=CN=C1.O>CN(C=O)C>[CH3:26][C:25]([Si:22]([CH3:24])([CH3:23])[O:1][C:2]1[C:3]([CH3:21])=[C:4]([CH3:20])[C:5]2[O:10][C:9]([CH3:17])([CH2:11][CH2:12][CH:13]=[C:14]([CH3:15])[CH3:16])[CH2:8][C:7](=[O:18])[C:6]=2[CH:19]=1)([CH3:28])[CH3:27]

Participants

6

Reactant 4

HCID 795ImidazoleHCID 962WaterHCID 28928tert-Butyldimethylsilyl chlorideHCID 19021837HCID 19021837, compound

Product 1

HCID 19021839HCID 19021839, compoundYield 72%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

A mixture of 2,3-dihydro-6-hydroxy-2,7,8-trimethyl-2-(4-methylpent-3-enyl )-4H-1-benzopyran-4-one (9.4 q, 34.3 mmole), tert-butyldimethylsilyl chloride (7.75 g, 51.5 mmole), and imidazole (6.99 g, 0.1 mole) were dissolved in 50 mL of dry DMF. The solution was stirred under nitrogen for about 18 hours, poured into water and extracted with ether. The organic layers were dried (brine, MgSO4) and concentrated in vacuo. The crude material was purified by flash chromatography (gradient 20:1 to 10:1 hexanes:ether) to give the title compound as a colorless oil (9.9 g, 24.6 mmole, 72%): 1H NMR (CDCl3) δ 0.20 (s, 6H), 1.0 (s, 9H), 1.37 (s, 3H), 1.55 (s, 3H), 1.55-1.60 (m, 1H), 1.65 (s, 3H), 1.74-1.84 (m, 1H), 2.0-2.1 (m, 2H), 2.14 (s, 3H), 2.16 (s, 3H), 2.63 (ABq, J=16.5 Hz, 2H), 5.07 (t, J=7.0 Hz, 1H), 7.09 (s, 1H); MS m/e 403 (MH+).

Workup

  1. extractionextracted with ether
  2. dry with materialThe organic layers were dried (brine, MgSO4)
  3. concentrationconcentrated in vacuo
  4. customThe crude material was purified by flash chromatography (gradient 20:1 to 10:1 hexanes:ether)

Sources & evidence

ORD record
ord-e483709018bd46a7bf89ad6bf0b40f39
Source dataset
uspto-grants-1994_06
Patent number
US05318993

Reaction notes

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