How to Avold Explosions when Heating Small Sealed Tubes Reactions in small closed glass containers at high temperatures are often tedious due to the difficulties in sealing and re-opening thick-walled Pyrex tubing. We suggest here a very simple device which allows even standard sealed NMR tubes to be used at temperatures as high as 180' C with liquid samples or solvents as volatile as methanol. The method employs a reusable, screwcapped, thick-walled test tuhe as a high-pressure containment vessel. The sealed tuhe containing the solution to be heated is introduced into a SVL test tuhe (1.8 mm wall thickness, from Carnick: tuhe, 703-01;cup 708-67) which is partly filled with the solvent used for the reaction. Thus pressure within the sealed tube is equalized on the outside during heating; and this prevents the sealed tuhe from exploding.
-SVL
sealed tube solvent
J. Cossy A. Flegenbaum Laboratoire de Photochlmie. U.A. 459 U. E. R. Sclen~es,51062 Reims Cedex, France
1014
Journal of Chemical gducation
+ ~oduct
tube
SoIYent oil both
