A simple synthetic procedure is provided for the quinidinium salt cited in the title. It is usually worthwhile saving such procedures for future reference. The procedure for the synthesis of N-(4,5-dimethoxybenzyl-2-nitrobenzyl) quinidinium bromide is shown below, as described in Adamo M.; (Royal College of Surgeons in Ireland) US Patent 9,593,071, 14-Mar-2017.
To a suspension of quinidine (650 mg, 2.0 mmol, 1.0 eq.) in THF (12.0 mL) 1-bromomethyl-4,5-dimethoxy-2-nitro-benzene (0.31 mL, 2.6 mmol, 1.3 eq.) was added. The resulting mixture was heated at 60 C for 16 h. The reaction was diluted with dichloromethane (10 mL) and washed with water (3×15 mL). The organic phase was dried over sodium sulfate and the solvent evaporated under reduced pressure. The crude material was purified by column chromatography (chloroform/methanol 95:5) affording the title compound as a purple solid (650 mg, 90% yield).
If you need to optimize the choice of phase-transfer catalyst for your commercial process, now contact Marc Halpern of PTC Organics Inc.
About Marc Halpern
Dr. Halpern is founder and president of PTC Organics, Inc., the only company dedicated exclusively to developing low-cost high-performance green chemistry processes for the manufacture of organic chemicals using Phase Transfer Catalysis. Dr. Halpern has innovated PTC breakthroughs for pharmaceuticals, agrochemicals, petrochemicals, monomers, polymers, flavors & fragrances, dyes & pigments and solvents. Dr. Halpern has provided PTC services on-site at more than 260 industrial process R&D departments in 37 countries and has helped chemical companies save > $200 million. Dr. Halpern co-authored five books including the best-selling “Phase-Transfer Catalysis: Fundamentals, Applications and Industrial Perspectives” and has presented the 2-day course “Practical Phase-Transfer Catalysis” at 50 locations in the US, Europe and Asia.
Dr. Halpern founded the journal “Industrial Phase-Transfer Catalysis” and “The PTC Tip of the Month” enjoyed by 2,100 qualified subscribers, now beyond 130 issues. In 2014, Dr. Halpern is celebrating his 30th year in the chemical industry, including serving as a process chemist at Dow Chemical, a supervisor of process chemistry at ICI, Director of R&D at Sybron Chemicals and founder and president of PTC Organics Inc. (15 years) and PTC Communications Inc. (20 years). Dr. Halpern also co-founded PTC Interface Inc. in 1989 and PTC Value Recovery Inc. in 1999. His academic breakthroughs include the PTC pKa Guidelines, the q-value for quat accessibility and he has achieved industrial PTC breakthroughs for a dozen strong base reactions as well as esterifications, transesterifications, epoxidations and chloromethylations plus contributed to more than 100 other industrial PTC process development projects.
Dr. Halpern has dedicated his adult life to his family and to phase-transfer catalysis (in that order!).
