A Novel Large Scale Hydrogenation Strategy of N,N-Dimethyl 4-(Acetoxy- 3-Nitrophenylmethyl)-1-H-lmidazole-1 Sulfonamide, a Key Intermediate in the Synthesis of ABT-866

A simple and versatile 4-station multiple hydrogenator was constructed to effectively analyze a broad range of reaction conditions, Figure 1 (5-6). The four individual reactors are equipped with argon and hydrogen supplies, as well as sampling and venting valves. Each reaction port has an attached glass pressure flask containing a magnetic stir bar, as well as an external water bath with temperature control. The delivery of different pressures of reactive gas to the individual reactors was supplied from a main source via a regulator, a relief valve set for 70 psi, and a gas manifold. The apparatus is compact, safe, and suitable for hydrogenations on scales ranging from micromoles up to a mole of material.