Iodine → (+,-) Trans Propane-2-sulfonic Acid [2-(4-iodo-phenyl)-cyclopentyl]-amide

HRID 989486

Reaction equation

[C:1]1([C@@H:7]2[CH2:11][CH2:10][CH2:9][C@H:8]2[NH:12][S:13]([CH:16]([CH3:18])[CH3:17])(=[O:15])=[O:14])[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.S(=O)(=O)(O)O.II.O=[I:27](OI(=O)=O)=O.S(=O)(O)[O-].[Na+]>C(O)(=O)C>[I:27][C:4]1[CH:3]=[CH:2][C:1]([C@@H:7]2[CH2:11][CH2:10][CH2:9][C@H:8]2[NH:12][S:13]([CH:16]([CH3:18])[CH3:17])(=[O:15])=[O:14])=[CH:6][CH:5]=1

Participants

Conditions

Temperature: 90 °C

Procedure

(+,−) Trans-propane-2-sulfonic acid (2-phenyl-cyclopentyl)-amide (0.52 g, 1.47 mmol, prepared in example 1) was dissolved in 30 mL of glacial acetic acid. To this solution was added concentrated sulfuric acid (0.16 mL, 1.61 mmol) at room temperature followed by iodine (0.19 g, 0.74 mmol), and diiodine pentoxide (0.20 g, 0.59 mmol). The reaction was then protected from light and heated to 90° C. and stirred for 22 hours. To the dark brown reaction mixture was slowly added 10% aqueous sodium bisulfite. The mixture was cooled to 0° C. for 1 hour and a light brown solid collected by filtration. The solid was dissolved in warm diethyl ether and washed with water (2×), then saturated sodium bicarbonate (1×). The organic layer was separated, dried (Na2SO4), filtered and concentrated in vacuo to give 435 mg (75%) of the title compound. The NMR was consistent with the assigned structure.

Workup

temperatureThe mixture was cooled to 0° C. for 1 hour
filtrationa light brown solid collected by filtration
dissolutionThe solid was dissolved in warm diethyl ether
washwashed with water (2×)
customThe organic layer was separated
dry with materialdried (Na2SO4)
filtrationfiltered
concentrationconcentrated in vacuo

Sources & evidence

ORD record: ord-1340a906f63c415a8cfb501561f1444f
Source dataset: uspto-grants-2003_10
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US06639107B1

Linked notes

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