Knowledge Bank

“The absorption spectra of solutions of amides in binary solvents have been observed over the range 1--10,000 atmospheres. Mixed solvents such as chloroform-Freon 11 $(CFCla)$ and benzene-Freon 11 were used since they not only satisfy the usual requirements for spectroscopic solvents, but also remain liquid over a wide composition range at these pressures. Unsubstituted amides, N-substituted amides, imides and compounds with other structural features were studied. Of special interest are the solutions of N-substituted amides in solvents containing benzene, where a complex, apparently involving both the amides and benzene, is $formed1$. The frequency shifts and intensity changes of the various bands can be correlated with the relative stabilities of the various solute species.”