I want to prepare DPMK initiator for my polymerizations. Please give me a pdf file of the journal necessary.
1, 1-Dipheynylmethyl Potassium is a salt of potassium with t-alcohol. Take 1, 1-Dipheynylmethyl alcohol in dry ether /THF then add required equimolar molar quantity of fresh potassium metal till it is completely dissolved to form salt of alcohol.
There seems to be a missunderstanding. Diphenylmethyl pottassium is not the salt of the diphenyl methylalcohol, but the reaction product of diphenylmethane and pottassium.
Fopr preparation, use a high vacuum line.Prepare a potassium mirror, by heating (sublimating) in vacuum a small amount of potassium.
Add your solution of diphenylmethane in dry THF to the K-mirror. You should obtain a red color uponn formation of the DPM-anion after some stirring. Transfer the solution into a ampoulle through a frit to remove excess of pottassium.
The activity of the solution must be determined in separate experiments (e.g. polymerization of PMMA and comparing the expected with the true number average molar mass) .
All reactions must be carried out under rigorous exclusion of moisture and air.
Sorry, I just found one reference (in German, http://www.chemie.uni-bayreuth.de/mcii/de/forschung/html/26845th.pdf).
Thank You Mr. Wolfgang Radke, it seems that the script of the file is in German language.
However google translate helped me to some extent. Thank You.
Sorry for the wait. The reference is for making fluorenyl potassium, a closely related compound.
The classical synthesis of DPMK is the indirect metallation via potassium naphthenide. Simply, under dry and inert conditions, dissolve a slight excess of naphthalene in dry THF, and add potassium metal (1 eq.). It will dissolve in about an hour to a deep green solution (no H2 produced, it's entirely redox). Once all the potassium is consumed, add a slight excess of dry diphenylmethane. This is a slow reaction, and it will turn red over the course of a few days (again, no H2 produced, the hydrogen is transferred to the naphthalene to make dihydronaphthalene). It is best to wait longer than you think. This can be used as an initiator, although you may want to titrate it.
- Badges
- Science topic