Jamaat Salaah at home with non-mahram females

Islam instructs that strict purdah be observed between na mahram males and females. There should be no contact or interaction unnecessarily between them. Similarly Islam commands that men perform their Salaah in the Musjid with Jamaat and women perform their Salaah individually at home. It is impermissible for a Baaligh male to perform his Salaah at home without a valid Shar'ee reason. However, despite it being incorrect if na mahram women perform Salaah behind a na mahram male, the Salaah will be valid if the Imaam made niyyat for leading the women in Salaah.

And Allah Ta'ala (الله تعالى) knows best.