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Synthesis of a Weinreb amide.; N,N’-Dimethoxy-N,N’-dimethylsuccinamide.

SyntheticPage 803
DOI: 10.1039/SP803
Submitted Nov 02, 2015, published Nov 11, 2015
Jerome Husson (jerome.husson@univ-fcomte.fr)
A contribution from Institut UTINAM


			Reaction Scheme: <IMG src="/images/empty.gif">Synthesis of a Weinreb amide.<IMG src="/images/empty.gif">

Chemicals Used

N,O-dimethylhydroxylamine hydrochloride (TCI Chemicals)

Succinyl chloride (ACROS)

Triethylamine (Fisher Chemical)

Dichloromethane (Fisher Chemical)

Procedure

In a three-necked round bottomed flask fitted with an argon inlet, a thermometer and an addition funnel, are successively placed N,O-dimethylhydroxylamine hydrochloride (24.00 g), dichloromethane (270 mL) and succinyl chloride (12.9 mL). The resulting suspension is cooled to 0°C under argon and triethylamine (67 mL) is added dropwise at such a rate that internal temperature remains below 10°C. When addition is completed, reaction mixture is stirred at 0°C for two hours. The solution is then allowed to warm to room temperature and then poured onto saturated aqueous sodium bicarbonate solution (150 mL). The obtained slurry is filtered on a glass sintered funnel and the layers are separated. Aqueous layer is extracted with dichloromethane (2×75 mL). Organic layers are combined, washed with brine (50 mL), dried over anhydrous sodium sulphate and concentrated. The compound is obtained as a light brown solid (15.31 g; 64%)

Author's Comments

Weinreb amides are useful intermediates in the preparation of ketones by reacting with organometallic reagents. The compound so obtained is sufficiently pure to be used without further purification.

Data

1H NMR (300 MHz, CDCl3) ppm = 3.73 (6H, s); 3.17 (6H, s); 2.76 (4H, s).

13C NMR (75 MHz, CDCl3) ppm = 173.3; 61.1; 32.1; 26.3.

Lead Reference

Harding, M. et al. J. Chem. Soc., Perkin Trans. 1, 2002, 2403-2413.

Supplementary Information

e.g. Actual NMR spectra (as images or jdx files for interactive spectra), photographs of apparatus, TLC’s or crystals or videos. Please contact the ChemSpider team (ChemSpider-at-rsc.org) for help with this.
1 H NMR spectra (JH_258_1(H).pdf)
13 C NMR spectra (JH_258_1(C).pdf)

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Get structure file (.cdx, .sk2, .mol)

Keywords: amides, nucleophilic, substitution

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