Is it permissible to pray Dhuhr a quarter of an hour before Asr due to fasting and sleeping after Fajr until close to Asr?

The time for Dhuhr prayer begins when the sun declines from its zenith until the shadow of everything becomes equal to its height. It is not permissible to intentionally delay the Dhuhr prayer beyond this time unless there is a legitimate شرعي excuse, such as combining prayers during travel or due to illness. There is no sin in delaying it due to sleep. It is permissible to perform the Dhuhr prayer at the end of its time, but it is preferable to perform it at the beginning of its time, unless the heat is severe, in which case it is recommended to delay it (al-Ibrad). Congregational prayer is obligatory for men unless there is an excuse.