P-Acetanilide

Solutions of sodium or potassium nitrates in concentrated sulfuric acid can be used as a substitute for anhydrous mixed acid." 2,4,6-Trinitroaniline (picramide) has been synthesized via the addition of a solution of potassium nitrate in concentrated sulfuric acid to a solution of either o- or p-acetanilide in oleum. ... 

Figure 2-33. Left The centrosymmetric arrangement of acetanilide molecules of the crystal resulting in centrosymmetric crystal habit Right. The p-acetanilide molecules are aligned in a head-tail orientation resulting in the occurrence of a polar axis of the crystal habit [39], Both are reprinted with permission from 1981 American Chemical Society and D. Y. Curtin and I. C. Paul.

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