Safety Assessment for the Scale-up of an Oxime Reduction with Melted Sodium in Standard Pilot-Plant Equipment

A pilot-plant process is described for the reduction of 2-allyl cyclohexanone oxime with melted sodium in xylenes, toluene, and 4-methyl-2-pentanol. The trans/cis ratio was 3–4:1. Safety data are presented from a range of thermokinetic experiments (heat flow calorimetry, differential scanning calorimetry, and accelerating rate calorimetry). The process has been designed and developed to enable an expedient and safe scale-up in a standard enameled 100-L steel reactor and has been reproduced six times on 209 mol scale (each 4.8 kg sodium). Crystallization of the product 2-allyl cyclohexylamine with oxalic acid from the reaction mixture in tert-butyl methyl ether successfully avoided the yield losses associated with the isolation of the volatile free 2-allyl cyclohexylamine.