A robust six-step process for the synthesis of crizotinib, a novel c-Met/ALK inhibitor currently in phase III clinical trials, has been developed and used to deliver over 100 kg of API. The process includes a Mitsunobu reaction, a chemoselective reduction of an arylnitro group, and a Suzuki coupling, all of which required optimization to ensure successful scale-up. Conducting the Mitsunobu reaction in toluene and then crystallizing the product from ethanol efficiently purged the reaction byproduct. A chemoselective arylnitro reduction and subsequent bromination reaction afforded the key intermediate 6. A highly selective Suzuki reaction between 6 and pinacol boronate 8, followed by Boc deprotection, completed the synthesis of crizotinib 1.

This work describes the optimization and scale-up of a Buchwald−Hartwig amination reaction for the preparation of a pharmaceutical intermediate. This C− N bond formation is challenged by the use of a chiral primary amine, which both adds cost and favors formation of biaryl byproducts. In order to develop a scalable process, a number of factors had to be investigated including catalyst selection and stoichiometry of the chiral amine. These all needed to be optimized while maintaining low palladium levels in the isolated product. The reaction was found to be most effective using Pd(dba) 2 with BINAP and Cs 2 CO 3 in THF. When executed on 2.5 kg scale, these conditions provided 2.06 kg of the desired product in 80% yield with only 73 ppm residual palladium. To date, this process has been successfully executed to produce more than 12 kg of compound (S)-3.

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Process development and multikilogram synthesis of the monocyclic β-lactam core 17 for a novel pyridone-conjugated monobactam antibiotic is described. Starting with commercially available 2-(2,2-diethoxyethyl)­isoindoline-1,3-dione, the five-step synthesis features several telescoped operations and direct isolations to provide significant improvement in throughput and reduced solvent usage over initial scale-up campaigns. A particular highlight in this effort includes the development of an efficient Staudinger ketene–imine [2 + 2] cycloaddition reaction of N-Boc-glycine ketene 12 and imine 9 to form racemic β-lactam 13 in good isolated yield (66%) and purity (97%). Another key feature in the synthesis involves a classical resolution of racemic amine 15 to afford single enantiomer salt 17 in excellent isolated yield (45%) with high enantiomeric excess (98%).

This paper describes the synthesis of two amino-quinazolinediones which are potent gyrase/topoisomerase inhibitors and useful as antibacterial agents. The early scale-up work to prepare a chiral side chain on multigram scale and two different amino-quinazolinedione cores is detailed. The enabling synthesis for the side chain employed a previously reported Michael addition of MeNO 2 to an enantiomerically enriched δ-aminoenoate and a two-step de-oxygenation of a lactam. Key synthetic steps for core preparation and completion of the aminoquinazolinediones include dianion-promoted cyclization via intramolecular, nucleophilic aromatic substitution, electrophilic amination, nucleophilic aromatic substitution of the side chain to the core, deprotection and isolation of the hydrochloride salt in acceptable yield.