tert-Butanol → Magnesium 2-methylpropan-2-olate

Participants

Reaction Conditions

Reaction Steps

9.0 g (370 mmol) of powdered magnesium (Timminco <150 μm) were suspended in 480 g of water-free THF in a 1 liter double-walled glass reaction vessel with a reflex cooler, internal thermometer and drip funnel and was mixed with 1.9 g (11 mmol, 3 mol %) of anthracene. The mixture was then heated to 50° C. After approximately 20 minutes the solution became orange in colour due to the formation of the Mg-anthracene adduct. 51 g (750 mmol) of isoprene were then dipped in within 10 min, and stirring took place for 1.5 hours at an internal temperature of between 50 and 55° C. A sample was taken and was titrated for total base content: the base content of 0.29 mmol/g was equivalent to reaction of approximately 21% of the total magnesium used. A mixture of 58 g of t-butanol (780 mmol) and 6 g of isoprene (90 mmol) was then added within 130 minutes. In the course of this care was taken to see that the colour deriving from the Mg-anthracene complex did not disappear.

Provenance & Evidence