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29th August 2011 @ 02:00
RXN 002 - Resolution of rac-PZQamine with (-)-di-p-anisoyl-L-tartaric acid (MW46-6) to obtain S-(+)-PZQamine (MNR2-1)

See:
Hydrolysis of rac-PZQ (MW2-14)
Repetition: Synthesis of (+)-Di-p-anisoyl-D-tartaric acid (MW46-6)

MNR2-1%20scheme.png

MNR2-1%20table.PNG
Hazard and Risk Assessment:

HIRAC MNR2.pdf


reaction on 0930
reaction off 1300

rac-PZQamine (1.0 g, 4.94 mmol) and (-)-di-p-anisoyl-L-tartaric acid (2.07 g, 4.94 mmol) was dissolved in a mixture of isopropanol (20 mL) and water (2 mL) by heating. The solution was allowed to cool to room temperature and stand for 3 hours. The solid was then filtered and rinsed with IPA/water (5:1, 50 mL).

Crude salt (2.597 g, 4.18 mmol, 85 %)

The salt (2.597 g, 4.18 mmol) was dissolved in NaOH solution (2M, 75 mL) and extracted with DCM (75 ml x 2). The aqueous layer was pH adjusted to pH2 using 6M HCl - see below. The organic fractions were combined, dried over magnesium sulphate, filtered and concentrated under reduced pressure to give a cloudy white thick oil (0.263 g, 1.30 mmol, 26 %). The oil was taken up in refluxing IPA/Water (5:1, 10 mL) and left to stand overnight at room temperature. No crystals formed over night (too dilute?) so mixture was concentrated under reduced pressure and extracted with DCM (15 mL) and brine (15 mL), dried over magnesium sulphate, filtered and concentrated to give the oil as before. Upon drying on the high vac the oil slowly crystallized. Optical rotation of this showed the undesired enantiomer

MNR2-1 [α]D20 = -268° (c=1, DCM)

reaction not taken any further and moved onto MNR2-2

MNR2-1%20-%20resolved%20prodcut%20MNR3-1

1H NMR - resolved product
1H NMR -MNR2-1 - resolved product MNR3-1.pdf


Lab book page complete, MNR
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Attached Files
MNR2-1 scheme.png
HIRAC MNR2.pdf
MNR2-1 table.PNG
MNR2-1 - resolved prodcut MNR3-1.png
1H - mnr2-1 - resolved product mnr3-1.png
1H NMR -MNR2-1 - resolved product MNR3-1.pdf
mnr3-1 from mnr2-1.zip