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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 @ 02:51

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The yellow oil from last night was still fluid, but when the round bottom flask was touched, the crystals formed. Once all the oil had solidified, I put the flask on the hi-vac for about 2 hours and then took NMR. The NMR showed the product was accurately compound [3] and that it was pure, so I proceded with the hydrazine reaction, adapted from AEW 85-5. We had isolated 3.37 g 19.53 mmol of product [3], yield= 71.8% which was dissolved in 40 mL 190 proof EtOH to make an approximately 0.5M clear solution of [3] in EtOH. The solution was stirred under argon. 1 equivilant of hydrazine hydrate (1 mL of 20 M) was added, and immediately a colorchange from clear to transparent yellow happened. As it stirred, the solution  got gritty and opaquely light yellow. Note: NO REFULX was used, unlike in AEW's procedure, because we were afraid of a competing electrophile in the ester moiety. Aslo, we only used one equilivant at first of hydrazine for the same reason. After 5 hours of stirring under argon, TLC showed unreacted starting material, so a second equilivant of hydrazine hydrate was added, and the solution stirred overnight.
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