Reference of 33070-32-5, These common heterocyclic compound, 33070-32-5, name is 5-Bromo-2,2-difluorobenzodioxole, 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.
Preparation 67 2-(2,2-Difluorobenzo[d][1,3]dioxol-5-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane To a solution of 5-bromo-2,2-difluorobenzo[d][1,3]dioxole (1.5 g, 6.3 mmol) in N,N-dimethylformamide (12.7 mL) was added 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi(1,3,2-dioxaborolane) (1.6 g, 6.3 mmol), potassium acetate (1.9 g, 19.0 mmol), and (1,1′-bis(diphenylphosphino)ferrocene)-dichloropalladium(II) (0.3 g, 0.32 mmol). The reaction mixture was heated at 80 C. for 18 h, then the reaction mixture was diluted with Et2O and washed with water. The organic layers were separated, dried with Na2SO4, filtered, concentrated in vacuo, and purified by silica gel chromatography eluting with 0-100% acetone in hexanes to yield a brown oil (0.9 g, 50%): 1H NMR (400 MHz, DMSO-d6) delta 7.55 (d, J=8.0 Hz, 1H), 7.53 (s, 1H), 7.43 (d, J=8.0 Hz, 1H), 1.30 (s, 12H); 19F NMR (376 MHz, DMSO-d6) delta -49.26 (s); EIMS m/z 284.
The synthetic route of 33070-32-5 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; Dow AgroSciences LLC; Eckelbarger, Joseph D.; Epp, Jeffrey B.; Fischer, Lindsey G.; Lowe, Christian T.; Petkus, Jeff; Roth, Joshua; Satchivi, Norbert M.; Schmitzer, Paul R.; Siddall, Thomas L.; US2014/274701; (2014); A1;,
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