3:4: 5-Triiodobenzoates.
3:4: 5-Triiodobenzoates.
The derivatives enumerated above are unsatisfactory for alcohol – ethers, e.g., the mono-ethers of ethyleneglycol (” cellosolves “) and the mono-ethers of diethyleneglycol (” carbitols”) .Crystalline derivatives of alcohol – ethers are readily obtained with 3 : 4 : 5-triiodobenzoyl chloride ,
for example : Place 0-5 g. of 3 : 4 : 5-triiodobenzoyl chloride in a small test-tube,
add 0 • 25 ml. of the alcohol – ether and heat the mixture gently over a micro burner until the evolution of hydrogen chloride ceases (3-5 minutes). Pour the molten mass into 10 ml. of 20 per cent, alcohol to which crushed ice has been added. Some erivatives solidify instantly ; those which separate as oils change to solids in a few minutes without further manipulation. Recrystallise from rectified spirit (use 50 per cent, alcohol for esters of methyl and butyl ” carbitol “).
The following melting points have been recorded :—methyl cellosolve,
152° ; cellosolve, 128° ; iso-propyl cellosolve, 80° ; butyl cellosolve, 85° ;
phenyl cellosolve, 145° ; benzyl cellosolve, 104° ; methyl carbitol, 82°;
ethyl carbitol, 76° ; butyl carbitol, 54°.
Posted on June 10, 2010 at 8:26 am by dharmesh · Permalink
In: Reaction Mechanisms · Tagged with: 3:4: 5-Triiodobenzoates.
In: Reaction Mechanisms · Tagged with: 3:4: 5-Triiodobenzoates.