One of the key sites to search for new complex organic molecules in the interstellar medium (ISM) has turned out to be the star-forming, hot, molecular cloud core Sgr B2(N). I will present the first results of the EMoCA survey conducted toward this source with ALMA in its Cycles 0 and 1. This spectral line survey covers the 3 mm atmospheric window and aims at deciphering the molecular content of Sgr B2(N) in order to test the predictions of state-of-the-art astrochemical numerical simulations and to gain insight into the chemical processes at work in the ISM. I will report on the first detection of a branched alkyl molecule in the ISM. I will discuss the implications of this detection in terms of interstellar chemistry and its possible connection to the complex organic molecules found in meteorites.
