The creation of complex organic molecules in the interstellar medium (ISM) holds the key to understanding astrochemistry and the origins of life. Among these intriguing compounds is glyceraldehyde, a potential precursor to the building blocks of life.

While glyceraldehyde (HOCH2CH(OH)C(O)H) has eluded detection in the ISM, the existence of related substances across various astronomical settings hints at its possible formation in space.

In our groundbreaking study, we utilized the AutoMeKin tool to delve deep into the gas-phase chemical reaction networks of glyceraldehyde and its analogs, C3H7O3 and C2H5O2. By employing advanced computational methods, we mapped out reaction pathways at the wB97XD/Def2-TZVPP level of theory, calculating key rate coefficients using the competitive canonical unified statistical (CCUS) model. This approach considers multiple dynamic bottlenecks affecting reactions.

Our findings uncovered several barrierless routes that could lead to glyceraldehyde or related products. A particularly noteworthy pathway is the reaction between glyoxal (HCOHCO) and the HOCHCH2OH radical. Although both molecules remain undetected in the ISM, they efficiently produce glyceraldehyde and a formyl radical.

However, aside from this significant reaction, the majority of pathways for glyceraldehyde formation predominantly yield high-energy intermediates. These excited states are prone to rapid decomposition rather than stabilization by radiative emission in typical ISM environments.

This indicates that while the formation of glyceraldehyde is theoretically possible, it’s likely to be a fleeting and elusive process, making direct detection a challenge. In contrast, other products like formaldehyde and glycolaldehyde appear more prominently, aligning better with current observations in space.

As researchers continue to unfold the complexities of cosmic chemistry, these insights not only deepen our understanding of organic synthesis in the universe but also enhance our quest to uncover the origins of life.