Hydrochloric Acid → 4-[3-(p-Nitrobenzyloxycarbonyl)-2-oxopropyl]-azetidin-2-one

HRID 620431Notes

Reaction equation

HRID 620431 reaction equation
[Si]([N:8]1[CH:11]([CH2:12][C:13](=[O:28])[CH2:14][C:15]([O:17][CH2:18][C:19]2[CH:24]=[CH:23][C:22]([N+:25]([O-:27])=[O:26])=[CH:21][CH:20]=2)=[O:16])[CH2:10][C:9]1=[O:29])(C(C)(C)C)(C)C.Cl.P([O-])([O-])(O)=O.[K+].[K+]>CO>[N+:25]([C:22]1[CH:23]=[CH:24][C:19]([CH2:18][O:17][C:15]([CH2:14][C:13](=[O:28])[CH2:12][CH:11]2[NH:8][C:9](=[O:29])[CH2:10]2)=[O:16])=[CH:20][CH:21]=1)([O-:27])=[O:26]

Participants

5

Reactant 3

HCID 313Hydrochloric AcidHCID 24450Potassium Phosphate, DibasicHCID 12804721N-(t-butyldimethylsilyl)-4-[3-(p-nitrobenzyloxycarbonyl)-2-oxopropyl]-azetidin-2-one

Product 1

HCID 128047224-[3-(p-Nitrobenzyloxycarbonyl)-2-oxopropyl]-azetidin-2-oneYield 91%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

A solution of N-(t-butyldimethylsilyl)-4-[3-(p-nitrobenzyloxycarbonyl)-2-oxopropyl]-azetidin-2-one (5.17 g, 12.3 mMol) in methanol (55 ml) is treated with 1N hydrochloric acid (6.2 ml) and then kept at room temperature for 200 mins. The solution is treated with 1M dipotassium hydrogenphosphate (6.2 ml) and concentrated under vacuum. The residue is taken up in ethyl acetate (100 ml), washed with brine, dried over magnesium sulfate, filtered, and evaporated under vacuum. Triturating the resulting oil with diethyl ether yields 4-[3-(p-nitrobenzyloxycarbonyl)-2-oxopropyl]-azetidin-2-one (3.42 g, 91%) as an off-white powder: mp 50°-52°; IR (CH2Cl2) 3416, 1767, 1723, 1528, and 1352 cm-1 ; NMR (CDCl3) δ 2.60 (ddd, 1, J=1, 2.7, and 15.1, H3β), 2.77 (dd, 1, J=8.4 and 18.2, CHCH2CO), 3.13 (dd, 1, J=5.1 and 18.2, CHCH2CO), 3.20 (ddd, 1, J=2.4, 5.0, and 15.1, H3α), 3.57 (s, 2, COCH2CO2), 3.98 (m, 1, H4); 5.27 (s, 2, CH2Ar), 6.28 (or s, 1, NH), 7.53 and 8.23 (two d's, 4, J=8.5, ArH); mass spectrum m/e 306(M+), 264(M+-42), 237, 153, 125, 111, and 136.

Workup

  1. concentrationconcentrated under vacuum
  2. washwashed with brine
  3. dry with materialdried over magnesium sulfate
  4. filtrationfiltered
  5. customevaporated under vacuum
  6. customTriturating the resulting oil with diethyl ether

Sources & evidence

ORD record
ord-43a138e20fbe4e7caf4a966a0085b261
Source dataset
uspto-grants-1989_04
Patent number
US04820817

Reaction notes

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