Triethylamine → Methyl alpha-[4-benzyloxycarbonylthio-3-phthalimido-2-oxoazetidin-1-yl]-alpha-(1-benzyloxycarbonylethylidene)acetate

HRID 971504Notes

Reaction equation

[SH:1][CH:2]1[N:5]([C:6](=[C:11](O)[CH3:12])[C:7]([O:9][CH3:10])=[O:8])[C:4](=[O:14])[CH:3]1[N:15]1[C:19](=[O:20])[C:18]2=[CH:21][CH:22]=[CH:23][CH:24]=[C:17]2[C:16]1=[O:25].Cl[C:27]([O:29][CH2:30][C:31]1[CH:36]=[CH:35][CH:34]=[CH:33][CH:32]=1)=[O:28].C(N([CH2:42][CH3:43])CC)C>O1CCCC1>[CH2:30]([O:29][C:27]([S:1][CH:2]1[N:5]([C:6](=[C:11]([C:7]([O:9][CH2:10][C:43]2[CH:42]=[CH:23][CH:24]=[CH:17][CH:16]=2)=[O:8])[CH3:12])[C:7]([O:9][CH3:10])=[O:8])[C:4](=[O:14])[CH:3]1[N:15]1[C:19](=[O:20])[C:18]2=[CH:21][CH:22]=[CH:23][CH:24]=[C:17]2[C:16]1=[O:25])=[O:28])[C:31]1[CH:36]=[CH:35][CH:34]=[CH:33][CH:32]=1

Participants

Conditions

Temperature: -65 °C

Procedure

To a solution of methyl α-[4-mercapto-3-phthalimido-2-oxoazetidin-1-yl]-α-(1-hydroxyethylidene)acetate (100 mg) in tetrahydrofuran (3 ml) is added benzyl chloroformate (100 mg), and the mixture is cooled to -65° C. To the solution is added triethylamine (60 mg) and stirred for 1 hour. After warming to room temperature, the mixture is evaporated. Purification of the residue by chromatography over silica gel gives methyl α-[4-benzyloxycarbonylthio-3-phthalimido-2-oxoazetidin-1-yl]-α-(1-benzyloxycarbonylethylidene)acetate (160 mg). Yield: 94%. The product contains no isomer at position α. IR: νmaxCHCl3 1790, 1780, 1730 cm-1. NMR: δCDCl3 8.00-7.50m4H, 7.40s5H, 7.30s5H, 6.27d(5Hz)1H, 5.90d(5Hz)1H, 5.27s2H, 5.17s2H, 3.70s3H, 2.47s3H.

Workup

temperatureAfter warming to room temperature
customthe mixture is evaporated
customPurification of the residue by chromatography over silica gel

Sources & evidence

ORD record: ord-2f989e8266fa4a74beb946268af5d7bf
Source dataset: uspto-grants-1979_07
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US04160085

Reaction notes

Loading…