Bromide ion → HCID 20336567, compound

HRID 1706126Notes

Reaction equation

HRID 1706126 reaction equation
[CH3:1][S:2][CH:3]1[NH:6][C:5](=[O:7])[CH2:4]1.[H-].[Na+].[H][H].Br[CH2:13][C:14]#[C:15][C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][C:17]=1[C:22]([O:24][CH2:25][C:26]1[CH:31]=[CH:30][C:29]([O:32][CH3:33])=[CH:28][CH:27]=1)=[O:23].[Br-]>CN(C)C=O>[CH3:1][S:2][CH:3]1[N:6]([CH2:13][C:14]#[C:15][C:16]2[CH:21]=[CH:20][CH:19]=[CH:18][C:17]=2[C:22]([O:24][CH2:25][C:26]2[CH:31]=[CH:30][C:29]([O:32][CH3:33])=[CH:28][CH:27]=2)=[O:23])[C:5](=[O:7])[CH2:4]1

Participants

7

Reactant 5

HCID 259Bromide ionHCID 24758Sodium hydrideHCID 126772484-(Methylsulfanyl)azetidin-2-oneHCID 20336613(4-Methoxyphenyl)methyl 2-(3-bromoprop-1-yn-1-yl)benzoateHCID 178418361HCID 178418361, compound

Product 1

HCID 20336567HCID 20336567, compoundYield 26%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent2×

Procedure

4-Methylthioazetidin-2-one (470 mg., 4 mmole) was dissolved in dry dimethylformamide (10 ml.) and the solution was stirred at -20° with exclusion of moisture while sodium hydride (50% dispersion in oil, 200 mg., 4 mmole) was added. When evolution of hydrogen had ceased (ca 10 minutes), 3-bromo-1-[o-(p-methoxybenzyloxycarbonyl)-phenyl]-prop-1-yne (1.44 g., 4 mmole) in dry dimethylformamide (5 ml.) was added dropwise to the stirred mixture at -20°. After addition of the bromide was complete, the mixture was warmed to 0° and stirred at that temperature for 30 minutes. The mixture was poured into ice-water (50 ml.) and the aqueous mixture was extracted twice with ethyl acetate (50 ml. portions). The combined ethyl acetate extracts were washed three times with water (30 ml. portions). The solution was dried (magnesium sulphate) and the solvent was evaporated under reduced pressure to yield a yellow gum. The gum was chromatographed on silica gel (25 g.) using ethyl acetate/petroleum ether (b.p. 60°-80°) to give the title compound as a colourless gum (400 mg., 26% yield). (Found: M+, 395.11850. C22H21NO4S requires 395.11912). νmax (CHCl3): 1760 (β-lactam C=O), 1730 (ester C=O), 1620 and 1520 (aromatic C=C) cm-1. δ (CDCl3): 2.10 (s, 3H, SCH3), 2.91 (dd, J 15, J' 3 Hz, 1H, β-lactam CHH), 3.35 (dd, J 15, J' 6 Hz, 1H, β-lactam CHH), 3.75 (s, 3H, OCH3), 3.86 (d, J 16.5 Hz, 1H, NCHH), 4.42 (d, J 16.5 Hz, 1H, NCHH), 4.94 (dd, J 6, J' 3 Hz, 1H, β-lactam CH), 5.35 (s, 2H, OCH2Ar), 6.95 (d, J 8.5 Hz, 2H, Ar-H), 7.2-7.6 (m, 5H, Ar-H), 7.95 (m, 1H, Ar-H). m/e: 395 (M+, 1%), 348 (14), 274 (63), 205 (37), 168 (56), 159 (68), 158 (44), 122 (76), 121 (100).

Workup

  1. additionwas added
  2. additionwas added dropwise to the stirred mixture at -20°
  3. temperaturethe mixture was warmed to 0°
  4. extractionthe aqueous mixture was extracted twice with ethyl acetate (50 ml. portions)
  5. washThe combined ethyl acetate extracts were washed three times with water (30 ml. portions)
  6. dry with materialThe solution was dried (magnesium sulphate)
  7. customthe solvent was evaporated under reduced pressure
  8. customto yield a yellow gum
  9. customThe gum was chromatographed on silica gel (25 g.)

Sources & evidence

ORD record
ord-aee8d2b83f214e0096af4f44a4671dc1
Source dataset
uspto-grants-1980_06
Patent number
US04206120

Reaction notes

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