The formation and evolution of complex organic molecules in the early stages of solar-type protostars (Class 0 objects) is crucial as it sets the stage for the content in pre-biotic molecules of the subsequent proto-planetary nebula. In order to understand the chemistry of these Class 0 objects, it is necessary to perform interferometric observations which allow us to resolve the hot corino, that is the warm, dense inner region of the envelope of a Class 0 object, where the complex organic molecules are located. Such observations exist for only two objects so far, IRAS16293-2422 and NGC1333-IRAS2A and we present here Plateau de Bure interferometric maps of a third hot corino, NGC1333-IRAS4A, which show emission of the complex organic molecule CH3CN arising from a region of size ~0.8″/175 AU, that is, of the order of the size of the Solar System. Combining these high-angular resolution maps with prior single-dish observations of the same transitions of CH3CN indicates that extended emission is also present, and we investigate the implications for organic chemistry in hot corinos.
