Hilal bin Yasaf (may Allah have mercy on him) says that Sayyiduna Sa'd (may Allah be pleased with him) sought permission from the Prophet (peace and blessings be upon him) while standing directly facing the door. He said to him: "When you seek permission, do not face the door."
Both of these reports are mursal.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الأشربة والحد فيها / 17662