Processes for the production of chlorinated and/or fluonnated propenes provide good product yield with advantageous impurity profiles in the crude product. Advantageously, the processes may be conducted at lower temperatures than 600° C., or less than 500° C., so that energy savings are provided, and/or at higher pressures so that high throughputs may also be realized. The use of catalysts or initiators may provide additional enhancements to conversion rates and selectivity, as may adjustments to the molar ratio of the reactants.