AbstractA process for N‐butyl‐N‐(2‐nitroxyethyl)nitramine (BuNENA) was investigated: Step 1 involves N‐butyl‐ethanolamine addition to 98% HNO3 to form a salt mixture; Step 2 is addition of acetic anhydride/acetyl chloride catalyst to the salt mixture. A number of potential intermediates, by‐products, and decomposition products from this process were identified/synthesized for use as analytical standards. BuNENA process reaction pathways/mechanisms were elucidated, including the nature of the amine salt solution formed in Step 1. In addition, potential pathways that could account for by‐product formation were elaborated. A study of the consumption of acetyl nitrate in Step 2 was undertaken to prevent its build‐up.