Tetrahydrofuran → (3S,4R)-3-[1-(R)-t-Butyldimethylsilyloxyethyl]-4-(2-p-nitrobenzyloxycarbonylaminoethyl)thiomethylcarbonylmethylazetidin-2-one

HRID 355009

Reaction equation

HRID 355009 reaction equation
[N+:1]([C:4]1[CH:17]=[CH:16][C:7]([CH2:8][O:9][C:10]([NH:12][CH2:13][CH2:14][SH:15])=[O:11])=[CH:6][CH:5]=1)([O-:3])=[O:2].Br[CH2:19][C:20]([CH2:22][C@H:23]1[NH:26][C:25](=[O:27])[C@@H:24]1[C@H:28]([O:30][Si:31]([C:34]([CH3:37])([CH3:36])[CH3:35])([CH3:33])[CH3:32])[CH3:29])=[O:21].O1CCCC1.C([Li])CCC>CCCCCC.C(OCC)(=O)C.C(O)(=O)C>[Si:31]([O:30][C@@H:28]([C@@H:24]1[C@@H:23]([CH2:22][C:20]([CH2:19][S:15][CH2:14][CH2:13][NH:12][C:10]([O:9][CH2:8][C:7]2[CH:16]=[CH:17][C:4]([N+:1]([O-:3])=[O:2])=[CH:5][CH:6]=2)=[O:11])=[O:21])[NH:26][C:25]1=[O:27])[CH3:29])([C:34]([CH3:37])([CH3:35])[CH3:36])([CH3:33])[CH3:32]

Participants

8

Reactant 4

HCID 8028TetrahydrofuranHCID 3017625(4-Nitrophenyl)methyl (2-mercaptoethyl)carbamateHCID 14166264(3S,4R)-4-Bromomethylcarbonylmethyl-3-[1-(R)-t-butyldimethylsilyloxyethyl]-azetidin-2-oneHCID 178418339Butyllithium

Product 1

HCID 70528790(3S,4R)-3-[1-(R)-t-Butyldimethylsilyloxyethyl]-4-(2-p-nitrobenzyloxycarbonylaminoethyl)thiomethylcarbonylmethylazetidin-2-oneYield 76.3%

Reagents, catalysts & solvents 3

HCID 176Acetic AcidSolventHCID 8058HexaneSolventHCID 8857Ethyl AcetateSolvent

Conditions

Temperature
-78 °C

Procedure

0.536 g. of 2-(p-nitrobenzyloxycarbonylamino)ethylmercaptan was added to a mixture of 0.635 g. of bromomethylazetidin-2-one (48) and 20 ml. of dry tetrahydrofuran. The mixture was cooled to -78° C. and a solution of 1.18 ml of n-butyllithium in n-hexane was added thereto. The mixture was stirred at that temperature for 1.5 hours. Acetic acid (0.22 ml) was added to the reaction mixture. The mixture was then diluted with 380 ml of ethyl acetate and washed successively with water and an aqueous solution of sodium chloride, and was then dried over sodium sulphate. The solvent was distilled off under reduced pressure and the resulting oily residue was subjected to rapid chromatography using silica gel eluted with a 1:4 by volume mixture of benzene and ethyl acetate, to afford 0.718 g. (yield 76.3%) of the desired azetidin-2-one (49).

Workup

  1. washwashed successively with water
  2. dry with materialan aqueous solution of sodium chloride, and was then dried over sodium sulphate
  3. distillationThe solvent was distilled off under reduced pressure
  4. washeluted with a 1:4 by volume mixture of benzene and ethyl acetate
  5. customto afford 0.718 g

Sources & evidence

ORD record
ord-efe42f79f3824da1b6d88591d90be46c
Source dataset
uspto-grants-1983_03
Patent number
US04377591

Linked notes

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