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09-06-2016, First step in synthesis of the hetero-oxadiazole, reaction of 2-6 dichloropyrazine with malononitrile, following procedure from Nikishkin et al (2013)
09-11-2016, Work up of the second attempt at step 1
09-23-2016. Step 1 redo, on 5 gram scale
09-24-2016. Work up of 09-23-2016
09-29-2016, work up and purification of [4]
09/28/2016 Step 4, on a larger scale this time. Conversion of methyl 6-chloropyrazine-2-carboxylate [3] to methyl 6-hydrazineylpyrazine-2-carboxylate [4] using hydrazine according to AEW 85-5
10/07/2016 GC mass spec characterization of rxn from [4]->[5]
10/18/16: Trial work up of reaction of 6-chloropyrazinecarbonitrile and hydrazine
10/4/16: Trial of Step 4:Product [4] to Product [5]
10/6/16: Trial Synthesis of 6-hydrazinelypyrazine-2-carbonitrile and from 6- hydrazinelypyrazine-2-carboximidhydrazide from chloropyrazinecarbonitrile
9/12/16 Step 2 in synthesis. Going from [2]->[3]
9/13/16: Work-up of product [3] and TLC plates
9/15/16: Second Synthesis of Methyl 6-chloropyrazine-2-carboxylate [product 3]
9/18/16-9/20/16: Trial Synthesis of Methyl 6-hydrazineylpyrazine-2-carboxylate (Product 4)
9/22/16: Inconclusive Trial Synthesis of Methyl 6-hydrazineylpyrazine-2-carboxylate (Product 4)
9/25/16-9/27/16: Synthesis of Product 3, methyl 6-chloropyrazine-2-carboxylate
9/27/2016 Late Night
9/29/2016 HNMR of product 4, and HNMR of product 4 after D2O exchange 01/10/2016
9/8/16-Continued Synthesis of 2-(6-chloropyrazin-2(1H)-ylidene)malononitrile
CNMR so far
HNMR so far, of all relevant compounds
The Synthetic scheme of Hetero-oxadiazole Synthesis
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20th October 2016 @ 16:50

Perfrmed GC mass spec to see if the rxn from [4] to [5] prodcued any appreciable ammout of desired product. Recall that we were unable to isolate the percipitate from this reaction, so we were doubtful that we had any product, however TLC of the reaction mixture showed a mixture that could potentially include our product.

 

GC of the mixture showed 3 peaks, at 5.92, 13.43, and 14.44.

Screen Shot 2016-10-20 at 12.02.23 PM.png

 

Analysis of the 5.92 peak showed a molecular ion peak of m/z=172.0509, which corresponds to unreacted aldehyde 4-(difluoromethoxy)benzaldehyde.

Screen Shot 2016-10-20 at 12.02.33 PM.png

 

Analysis of the 13.43 peak showed a major peak corresponding to product [4] with mass of 168.9949, and although there were many peaks out past 300, none of them were very tall, they were all minor in concentration

Screen Shot 2016-10-20 at 12.02.40 PM.png

 

Lastly, analysis of the 14.44 peak showed nothing around 320 at all, which is where we would expect to see product [5]

Screen Shot 2016-10-20 at 12.02.47 PM.png

This GC mass spec analysis indicates to us that we did not successfully isolate product 5. We hypothesize that it was a percipitate that became stuck in our filter paper due to small quantity. We reccomend next time doing this experiment, starting with a large sample of product [4], at least 10x how much we started with.

Attached Files
Screen Shot 2016-10-20 at 12.02.23 PM.png
Screen Shot 2016-10-20 at 12.02.33 PM.png
Screen Shot 2016-10-20 at 12.02.40 PM.png
Screen Shot 2016-10-20 at 12.02.47 PM.png