Related Products of 6942-39-8, A common heterocyclic compound, 6942-39-8, name is Methyl 2-bromo-5-fluorobenzoate, molecular formula is C8H6BrFO2, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.
To a solution of methyl 2-bromo-5-fluorobenzoate (18.26 moles) in DMF (total vol. 9.2 L) was charged copper(I) cyanide (1.603 kg) in DMF (5 L) slurry and followed with a DMF flush (4 L). After being degassed, the reaction mixture was heated at 100 C. for 10-16 hours. The reaction mixture was monitored by HPLC (conversion was >98%). After being cooled to 50 C.-60 C., ethyl acetate (20 L) was added, and then 10% NH4OH-20% NH4Cl (22 L). The mixture was then transferred to a 100 L nalgene extractor. The 72 L round bottom flask was washed with 15 L of EtOAc and 15 L of water and transferred to the 100 L extractor. After phase cut, the aqueous layer was back-extracted with EtOAc (17 L) one time. The combined organic layers were washed with 10% NH4OH/20% NH4Cl:water (1:1, 3*10 L), 16% brine (8 L), concentrated, and solvent switched to MeOH (total vol. 22 L, KF=152.6 mug/mL). The resulting solution was used for next step. HPLC conditions: column: Zorbax, Rx C8 250*4.6 mm; temperature: 30 C.; detection at 210 nm; mobile phase: 0.1% aq H3PO4 (A)/MeCN (B); gradient: 90:10 (A)/(B) to 10:90 over 15 min, 10:90 hold for 5 min, 10:90 to 90:10 (A)/(B) over 10 seconds; flow rate: 1 mL/min; retention time for the desired monoester: 11.7 min. Evaporation of a sample to dryness gave a light yellow solid: 1H NMR (CDCl3) delta: 7.86-7.80 (m, 2H), 7.37 (td, J=8.5, 2.6 H, 1H), 4.02 (s, 3H); 13C NMR (100 MHz, CDCl3) delta: 164.3 (d, J=260 Hz), 163.3, 137.1 (d, J=10.0 Hz), 135.2 (d, J=10.0 HZ), 120.2 (d, J=30.0 Hz), 118.8 (d, J=20.0 Hz), 116.6, 109.0, 53.1.
The synthetic route of 6942-39-8 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; Lee, Jaemoon; Zhong, Yong-Li; US2004/220273; (2004); A1;,
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