Dutch architect. He came into contact with architecture through his uncle, the construction manager-carpenter Jan van Dalen. He studied as a pensioner of King Louis Napoleon with Percier and Fontaine in Rome, thus gaining a thorough knowledge of classical architecture. He also attended classes at the painter Martinus Schouman (1770-1848). Between 1816 and 1820 De Greef occupied the position of 'architect of the royal palaces'. In this function he designed the interior of the big ballroom and the courtyard of Noordeinde Palace in The Hague and the extension of Soestdijk Palace in Baarn. In 1820 he succeeded Abraham van der Hart as a city architect in charge of Amsterdam's 'city factory office' (Amsterdam knows a Jan de Greef street). As such, he was responsible for the construction of the Palace of Justice. His son, Bastiaan de Greef Janszoon (1818-1899), was later also a city architect of Amsterdam. //