(R)-N-(4-bromobenzylidene)-2-methylpropane-2-sulfinamide → (S)-N-((R)-(4-bromophenyl)(phenyl)methyl)-2-methylpropane-2-sulfinamide

HRID 1525273Notes

Reaction equation

[Br:1][C:2]1[CH:15]=[CH:14][C:5](/[CH:6]=[N:7]/[S@@:8]([C:10]([CH3:13])([CH3:12])[CH3:11])=[O:9])=[CH:4][CH:3]=1.[C:16]1([Mg]Br)[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1>C1COCC1>[Br:1][C:2]1[CH:15]=[CH:14][C:5]([C@@H:6]([C:16]2[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=2)[NH:7][S@:8]([C:10]([CH3:11])([CH3:12])[CH3:13])=[O:9])=[CH:4][CH:3]=1

Participants

Conditions

Temperature: -45 °C

Procedure

(R,E)-N-(4-bromobenzylidene)-2-methylpropane-2-sulfinamide, 18-b, (10 g, 34.84 mmol) was dissolved in anhydrous THF (100 ml). The mixture was then cooled to −45° C. and PhMgBr (34.84 ml, 69.68 mmol) was added dropwise. After addition, the mixture was allowed to stir at −45° C. for additional 4 h and warm to room temperature for another 2 h. TLC monitored the reaction and the time was prolonged if necessary. The mixture was quenched with saturated NH4Cl followed by extraction with ethyl acetate. The organic layer was dried over sodium sulfate and concentrated under vacuum. The residue was purified by column chromatography (petroleum ether/ethyl acetate=4/1) to provide the product, 22-a, (8 g, 63%). HPLC indicated that the diastereomer ratio is 96:4 after recrystallization once in hexane/ethyl acetate.

Workup

additionAfter addition
temperaturewarm to room temperature for another 2 h
customthe reaction
customThe mixture was quenched with saturated NH4Cl
extractionfollowed by extraction with ethyl acetate
dry with materialThe organic layer was dried over sodium sulfate
concentrationconcentrated under vacuum
customThe residue was purified by column chromatography (petroleum ether/ethyl acetate=4/1)

Sources & evidence

ORD record: ord-8cdf44e600db40d29722f3475d55fddc
Source dataset: uspto-grants-2015_07
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US09079930B2

Reaction notes

Loading…