I have been trying for a few weeks to prepare vinyl lithium in order to prep a higher order cuprate, to do a carbon-carbon bond formation with a tosylate. The reaction requires Vinyl lithium. This is where the problem starts...
Vinyl lithium can be purchased, but due to shipping regulations, would take about two months to arrive. Most of the methods available require the use of t-butyl lithium, which we also don't have available, and is subject to the same shipping restrictions as vinyl lithium.
We have tried metal-halogen exchange (n-BuLi and vinyl bromide) which has been done before, but conditions are unclear, and were not successful.
We have also tried direct metallation, with vinyl bromide and fine Li metal (1% Na as catalyst), however this was also unsuccessful.
Any suggestions for its preparation? Preferably from Vinyl bromide (as this is what i have available). There are other methods, such as deprotonation of ethene with superbase, however, reagent availability is a problem.
We got an alternate synthetic route, so its not urgent to find a solution, but some help in solving this problem would be appreciated!