Description
n-Hexyllithium [21369-64-2], C6H13Li, Mr 92.11, r 0.766 g/cm3 is a pyrophoric colorless and viscous liquid in the neat state. It is commercially available as a 33 % solution in technical-grade hexane. Its reactivity resembles that of n-butyllithium and it can thus principally be used for the same applications. An advantage is that it does not form gaseous byproducts in deprotonation reactions and on hydrolysis, but liquid hexane instead.
Synthesis
Lithium n-hexyl preparation is as follows: argon protection, to the 500L reactor into the 250L white oil, 21kg lithium flakes, slow stirring temperature to 180 , stirring 0.5h, accelerate the stirring speed of the reactor to 130 rpm, 180 stirring 1h, open the cooled to room temperature, pressure filtration to remove the white oil, n-hexane is transferred to the washing kettle, rinsed for 2-3 times, to obtain a relatively homogeneous lithium metal form (lithium sand). Under the protection of argon, add 20kg of n-hexane to 500L reactor, put in 7kg of lithium sand and 58g of L-proline under the condition of keeping argon released from the kettle, seal the lid and keep the positive pressure, open the venting valve to keep the pressure in balance, add 80kg of n-hexane to the reactor, slowly turn on the stirring; warm up the temperature to 55 , open the balancing valve, add 60kg of chlorinated n-hexane dropwise, and control the temperature of the reactor around 53-55 ; control the reaction kettle temperature around 53-55 ; control the reaction kettle. Control the temperature of reaction kettle at about 53-55; control the speed of reaction kettle at 130 rpm. After dropping, start to keep warm, keep warm for about 8 hours, cool down to room temperature and stand, filter with a sand plate funnel, the reactor and the filtrate were washed with n-hexane, and the n-hexyl lithium product with a concentration of 1.9M was obtained as 233L (89% yield).
