Methods and systems are provided for converting methane in a feed stream to acetylene. The hydrocarbon stream is introduced into a supersonic reactor and pyrolyzed to convert at least a portion of the methane to acetylene. The reactor effluent stream may be treated to convert acetylene to nitrogen based hydrocarbon compounds such as pyridines. The method includes the reaction of acetylene with ammonia and controlling the ratio of acetylene to ammonia to generate the desired nitrogen based hydrocarbon compound.