In 1436 Dufay composed the festive motet Nuper rosarum flores , one of his most famous compositions , which was sung at the dedication of Brunelleschi 's dome of the cathedral in Florence . In 1436 Dufay composed the festive motet Nuper rosarum flores , one of his most famous compositions , which was sung at the dedication of Brunelleschi 's dome of the cathedral in Florence , where Eugene lived in exile .