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3rd May 2012 @ 00:08
Mnr: 1-10
MNR4-1%20scheme.png
MNR4-1%20table.PNG

Hazard and Risk Assessment:
HIRAC MNR4.pdf


A solution of 3,4-dimethoxyphenethylamine (24.0 mL, 132 mmol) in ethyl formate (130 mL, 1590 mmol) was heated to reflux for 22 h. The remaining ethyl formate and the by-product ethanol were removed under reduced pressure to give yellow liquid.

The crude 2-(3,4-Dimethoxyphenyl)ethylformamide and triethylamine (55.4 mL, 397 mmol) were dissoved in dry DCM (240 mL) and phosphoryl chloride (12.3 mL, 132 mmol) was added dropwise added at 0°C. The mixture was then stirred for 1 h at 0°C and a further 4 h at room temperature.
The mixture was quenched with water and neutralized with NaHCO3 solution. The organic layer was separated and the aqueous solution was extracted DCM (250 mL x4). The organic layers were combined, dried over magnesium sulphate, filtered and evaporated afforded a dark brown oil.

*yield not noted

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Reaction repeated on 21/08/12 - MNR4-5

A solution of 3,4-dimethoxyphenethylamine (24.0 mL, 132 mmol) in ethyl formate (130 mL, 1590 mmol) was heated to reflux for 22 h. The remaining ethyl formate and the by-product ethanol were removed under reduced pressure to give yellow liquid.

The crude 2-(3,4-Dimethoxyphenyl)ethylformamide and triethylamine (55.4 mL, 397 mmol) were dissoved in dry DCM (240 mL) and phosphoryl chloride (12.3 mL, 132 mmol) was added dropwise added at 0°C. The mixture was then stirred for 1 h at 0°C and a further 4 h at room temperature.
The mixture was quenched with water and neutralized with NaHCO3 solution - the reaction took a lot of quenching which was worrying. The organic layer was separated and the aqueous solution was extracted DCM (300 mL x4). The organic layers were combined, dried over magnesium sulphate, filtered and evaporated afforded a dark brown oil.

Crude NMR showed product compared to MNR4-3

mnr4-5_crude_1H.pdf
mnr4-3_dry.pdf


Crude TLC - 40%EtoAc/Hex

SANY0227.JPG


Column:- short column 20-30% EtOAc?Hex - product spot comes out before the yellow colour in the column starts to move, unexpected.

(250-500 mL fraction) Fracs 2-4 - 21.846 g, 114 mmol, 79%

frac2 flask - 8.169 g
frac3-4 flask - 13.677 g

The two fractions were kept apart as frac3-4 was slightly coloured although still only showing one spot by TLC. NMR shows that the two samples are identical.

NMR

mnr04-5_frac2_1H.pdf


mnr04-5_frac3-4_1H.pdf


*lab book page complete and closed 23/8/12
Attached Files
mnr4-3_dry.pdf
mnr4-5_crude_1H.pdf
SANY0227.JPG
mnr04-5_frac2_1H.pdf
mnr04-5_frac3-4_1H.pdf