https://www.thevespiary.org/rhodium/Rhodium/chemistry/red-al.nitrostyrenes.html (https://www.thevespiary.org/rhodium/Rhodium/chemistry/red-al.nitrostyrenes.html)
On the page in the experimental section there is stated:
Typically, a solution of the substituted benzaldehyde (1 mmol) and NH4OAc (1.25 mmol) in nitroethane was refluxed for the specified time. The mixture was cooled immediately in liquid N2 or Acetone-solid CO2, diluted with CH2Cl2, and filtered while cold. Solvent was removed in vacuo, and the remaining beta-nitrostyrene was recrystallized by known procedures6.
AFAIK the given procedure would give the corresponding nitropropene and not the nitrostyrene...