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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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30th September 2016 @ 03:13

In the morning, TLC showed the reaction had completed. This TLC is shown below. Lanes from top to bottom are starting material: product [3], co spot, and reaction mixture. Eluent was 7:1 EtOAc:Hexanes.   Seeing that the reaction had gone to completion, we followed the work up described in AEW 85-5, and first rotary evaporated our mixture to yield a pale yellow solid. We then tried to dissolve it in 20 mL deionized water and 27 mL EtOAc: however a large ammount of yellow percipitate crashed out immediately. We used vacuum filtration to remove this solid, then separated the organic from aqueous phases. Upon setting up the vacuum filtration, a lab error was made and the percipitate spilled all over the lab bench before extra solvent could be used to wash product from the percipitate. This will effect yield. The aqueous phase was extracted thrice with 30 mL of EtOAc. The organic layers were combined and washed twice with 20 mL brine, then dried over Na2SO4. The solvent was evaporated under reduced pressure to yield a thin layer of white powdery crust. The product was dried for 20 min on high vac and an NMR was taken. Once the NMR sampel was removed, it was left on the high vac overnight.

Perliminary analysis of NMR indicated good liklihood of successful synthesis but a more percise characterization of [4] is needed by GCMS

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