This is what motivated the famous Miller-Urey experiment, but Miller-Urey atmospheres actually produce a lot of "goo" that makes the resulting soup unusable and unproductive. Currently suggested alternatives to produce chemically reduced feedstocks like HCN include lightning and meteoritic impact events. The idea for the impacts is that the iron in the impact vaporizes an already present ocean, which makes CH4, which then reacts with UV light to produce HCN. See attached figure from Benner+2020.
The problem is we have no way to test this, since >4.5 Gyr of tectonic activity on Earth have erased essentially all evidence from this time. #Exoplanets to the rescue! 😀 Hydrogen-rich atmosphere have large scale heights, so if such reduced post-impact atmospheres would be common, we should see it with exoplanet telescopes like #JWST, and possibly with #Ariel. Attached a figure from Rimmer+2019, showing potential ethylene and acetylene features in a post-impact atmosphere.