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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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28th September 2016 @ 01:55

Due to lack of product [4] to continue with, we will redo the steps up to that point on a 5 gram scale. 

Today, 5 g 34.4 mmol of 2,6 dichloropyrazine [1] were dissolved in 100 mL dry THF and left under argon. In a 3 neck flask, 4.434 g malononitrile (1 equiv) was disolved under argon in 230 mL dry THF. An aparatus was constructed to pump argon through the 3 neck flask and out through a bubbler in mineral oil. While stirring and while argon was flowing to the bubbler, 2.26 g NaH (60%) was added in small portions. Solution bubbled and turned from amber to a dirty orange brown color. After stirring for an hour after the last of the NaH was added, the solution of [1] was added in small squirts thruogh a rubber septum into the 3 neck flask. As this was added, a yelow color slowly grew into the solution. A reflux was set up for 20 hours under a balloon of argon (the bubbling aparatus was discontinued after final addition of NaH). Upon checking midway through the reflux, the solution was an opaque yellow, as expected.