THE EFFECT OF PRESSURE ON THE MELTING POINT OF SODIUM HALIDES. REACTIONS OF PHENYL ISOCYANATE AT HIGH PRESSURES.
Final rept. on high pressure basic research programs, 1 Apr 64-31 Mar 65,
ALLIED CHEMICAL CORP MORRISTOWN N J CENTRAL RESEARCH LAB
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The D.T.A. technique was used to obtain the fusion curves of NaBr, NaCl, and NaF to pressures of 12, 43 and 45 kilobars respectively. The constants c and A of the Simon melting equations were computed from the experimental results. At 16 Kb. and a temperature range of 175-225C phenyl isocyanate was converted to its cyclic dimer 1,3-diphenyl-2,4-uretidinedione in greater than 90 yield. The dimerization reaction was favored by pressure. At higher pressures the temperature range was extended. Both the cyclic trimer triphenyl isocyanurate and another dimer of phenyl isocyanate 3-phenyl -2,4-dioxo-tetrahydroquinazoline were the principal products formed at 16 Kb. and temperatures equal to or greater than 275C. At these higher temperatures CO2 was the sole gaseous product. This gas may arise by pyrolysis of yet another phenyl isocyanate dimer having a four membered ring lactone structure. At 8 Kb. and 250C the major product of the reaction is thought to be a 21 cyclic trimer of phenyl isocyanate and diphenylcarbodiimide. Author
- Inorganic Chemistry
- Organic Chemistry
- Physical Chemistry