Does the idea of praying 5 times a day come from the Qur'an?

The concept of praying five times a day is indeed supported by the Qur'an, specifically in the verse: Establish worship at the going down of the sun until the dark of night, and (the recital of) the Qur'an at dawn. Lo! (the recital of) the Qur'an at dawn is ever witnessed. 17:78. This verse outlines the times of prayer, indicating that there are prayers performed from sunset until night and at dawn.

Additionally, Shia sources elaborate on this practice. In Al-Kafi, it is narrated: I once asked abu Ja‘far, ‘Alayhi al-Salam, about how much of Salat (prayer) Allah, most Majestic, most Glorious, has made obligatory. He (the Imam) said, ‘During one day and night five Salat (prayer) are made obligatory.’ Al-Kafi 3:4790. This shows that the five daily prayers are a specific command from Allah, with the Imam confirming that these prayers are named and explained in the Qur'an.

Furthermore, another verse that reinforces the importance of prayer is: If only there had been among the generations before you men possessing a remnant (of good sense) to warn (their people) from corruption in the earth, as did a few of those whom We saved from them! The wrong-doers followed that by which they were made sapless, and were guilty. 11:116. This verse emphasizes the need for guidance and the righteous actions, including prayer, that are essential for a community's moral and spiritual health.

Thus, the structure of the five daily prayers is derived from the Qur'an and is further clarified through the teachings of the Prophet Muhammad ﷺ and the Imams.