Bromhydrol → 2,2,2-Trichloroethyl 2-methyl-7-(2-phenylacetamido)-3-cephem-4-carboxylate

HRID 1764000Notes

Reaction equation

HRID 1764000 reaction equation
[CH3:1][C:2]12[CH2:15][C:6]1([C:7]([O:9][CH2:10][C:11]([Cl:14])([Cl:13])[Cl:12])=[O:8])[N:5]1[C:16](=[O:28])[CH:17]([NH:18][C:19](=[O:27])[CH2:20][C:21]3[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=3)[C@H:4]1[S:3]2.[Br-].[Al+3].[Br-].[Br-]>ClCCl>[CH3:1][CH:2]1[CH:15]=[C:6]([C:7]([O:9][CH2:10][C:11]([Cl:12])([Cl:13])[Cl:14])=[O:8])[N:5]2[C:16](=[O:28])[CH:17]([NH:18][C:19](=[O:27])[CH2:20][C:21]3[CH:22]=[CH:23][CH:24]=[CH:25][CH:26]=3)[C@H:4]2[S:3]1

Participants

4

Reactant 2

HCID 166749BromhydrolHCID 128339582,2,2-Trichloroethyl 2-methyl-2,3-methylene-6-(2-phenylacetamido)penam-3-carboxylate

Product 1

HCID 705273932,2,2-Trichloroethyl 2-methyl-7-(2-phenylacetamido)-3-cephem-4-carboxylateYield 80.4%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent2×

Procedure

A solution of 2,2,2-trichloroethyl 2-methyl-2,3-methylene-6-(2-phenylacetamido)penam-3-carboxylate (0.92 g.) in dried dichloromethane (5 ml.) was dropwise added at -10° C. over about 5 minutes to a solution of aluminum bromide (0.8 g.) in dried dichloromethane (10 ml.) and the mixture was stirred for 2 hours at room temperature. After the reaction was completed, the reaction mixture was washed in turn with 2% hydrochloric acid, a sodium bicarbonate aqueous solution and a saturated sodium chloride aqueous solution and then dried over magnesium sulfate, after which the solvent was distilled off under reduced pressure. The residual crystals were washed with ether and dried to give 2,2,2-trichloroethyl 2-methyl-7-(2-phenylacetamido)3-cephem-4-carboxylate (0.74 g.), mp 175° to 178° C. And the residue obtained by concentrating the ether washing was purified by column chromatography on silica gel to give 2,2,2-trichloroethyl 2-methyl-7-(2-phenylacetamido)-3-cephem-4-carboxylate (0.05 g.), mp 118° to 120° C., which is a stereoisomer at 2 position of the above obtained 2,2,2-trichloroethyl 2-methyl-7-(2-phenylacetamido)-3-cephem-4-carboxylate, mp 175° to 178° C., and 2,2,2-trichloroethyl 2-methyl-7-(2-phenylacetamido)-2-cephem-4-carboxylate (0.05 g.), mp 136° to 137° C. The above obtained 2,2,2-trichloroethyl 2-methyl-7-(2-phenylacetamido)-3-cephem-4-carboxylate, mp 118° to 120° C., was recrystallized from benzene to give crystals, mp 120° to 123° C.

Workup

  1. washthe reaction mixture was washed in turn with 2% hydrochloric acid
  2. dry with materiala sodium bicarbonate aqueous solution and a saturated sodium chloride aqueous solution and then dried over magnesium sulfate
  3. distillationafter which the solvent was distilled off under reduced pressure
  4. washThe residual crystals were washed with ether
  5. customdried

Sources & evidence

ORD record
ord-84dd9702dc91464cb26d2a73e3eba5a7
Source dataset
uspto-grants-1978_09
Patent number
US04113940

Reaction notes

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