Is the issue that the exported .JPG does not Match the .PSD file?
What Color Model are you selecting when you export the PSD from Illustrator?
Illustrator defaults to CMYK, if you export a CMYK image (.JPG) and try to use it on the web, the colors will not match. Make sure you select an RGB color profile before exporting your .JPG.
You should be able to select RGB when exporting the PSD file, if not once in Photoshop, go to Image > Mode > RGB Color.
