All Flask and Syringes were washed with acetone and allowed to dry to remove residual water. Reaction was performed on a gram scale (3g of my aniline)
First I stirred my aniline into Heptane, resulting in a white suspension. I then purged the septum sealed flask with Argon for 10 minutes. I prepared
to add my butyllithium with proper handling, withdrawing it under argon, etc.
When I added the butyllithium through syringe at room temperature, the flask temperature rose by about 20-30C, and the white suspension of my reagent
initially became cakey/filmy at points, indicating something was happening, but this evened out after about 5 minutes of stirring, at which point the
solution was creamy/milky white. I thought it was odd that the procedure called for heating at 85c, especially considering some reaction did appear to
happen upon immediate addition, but figured it was because the reagent doesn't dissolve in the Hexane, so additional time/heat was given due to it
being heterogeneous in nature. I let this stir 2 hours per the procedure.
After this, I then used a syringe to add my Bromoheptane compound. The original paper did not indicate that airfree techniques were used during this
step, but I decided to do so anyways to hopefully eliminate any potential oxygen reaction. Prior to this addition, some of the
material on the walls of the flask began to turn green, which I assumed was from degradation of the lithiation reagent from heat, however this was
relatively minor, but did become more green over the 12 hours. The overall stirring mixture remained relatively white.
Workup: I first added a slight amount of water through syringe to ensure there was no risk of fire and all lithium reagent destroyed.
I then added the full amount as specified and worked up exactly according to procedure. The solution/mixture was notably greenish at this point, and
when concentrated in the Rotary Evaporator it took on a very dark green / near black apperance. Resulting a slime which was not able to be
recrystallized at all in the solvent used in the paper, and hardly able to be poured out of the flask to be weighed.
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