34941-90-7Relevant articles and documents
Dehalogenation degradation method for halogenated pyridine compound
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Paragraph 0019; 0020, (2016/12/16)
The invention provides a dehalogenation degradation method for a halogenated pyridine compound. The halogenated pyridine compound is adopted as a raw material, alcohol is adopted as a hydrogen source, water is adopted as a solvent, reacting is carried out for 3-10 h under normal pressure at the temperature of 20 DEG C to 120 DEG C under the action of a supported catalyst, and the halogenated pyridine compound is subjected to dehalogenation degradation in situ through water phase hydrogen production. A pyridine ring of the halogenated pyridine compound at least contains an F or Cl or Br or I substituent group. The supported catalyst is composed of an active component and a carrier, the active component is composed of a mixture of transition metal and other metal, the transition metal is one of Rh, Pd, Pt and Ni, and other metal is one of Se, Ca, Ba, La and Ce. The carrier is one of activated carbon, kieselguhr, zeolite, gamma-Al2O3, AlF3 and MgO. H2 is not directly used as a reduction agent, activated hydrogen is prepared through in-situ catalysis to directly participate in reacting, the advantages of being high in reaction activity, high in selectivity, high in safety, environmentally friendly and the like are achieved, and good application prospects are achieved.
Removal of fluorine from and introduction of fluorine into polyhalopyridines: An exercise in nucleophilic hetarenic substitution
Bobbio, Carla,Rausis, Thierry,Schlosser, Manfred
, p. 1903 - 1910 (2007/10/03)
Starting from six industrially available fluorinated pyridines, an expedient access to all three tetrafluoropyridines (2-4), all six trifluoropyridines (5-10), and the five non-commercial difluoropyridines (11-14 and 16) was developed. The methods employed for the selective removal of fluorine from polyfluoropyridines were the reduction by metals or complex hydrides and the site-selective replacement by hydrazine followed by dehydrogenation-dediazotation or dehydrochlorination-dediazotation. To introduce an extra fluorine atom, a suitable precursor was metalated and chlorinated before being subjected to a chlorine/ fluorine displacement process.
Rerouting nucleophilic substitution from the 4-position to the 2- or 6-position of 2,4-dihalopyridines and 2,4,6-trihalopyridines: The solution to a long-standing problem
Schlosser, Manfred,Rausis, Thierry,Bobbio, Carla
, p. 127 - 129 (2007/10/03)
(Chemical Equation Presented) 2,4-Difluoro-, 2,4,6-trifluoro-, and 2,3,4,6-tetrafluoropyridine undergo nucleophilic substitution preferentially if not exclusively at the 4-position. However, after the introduction of a trialkylsilyl group at C-3 or C-5, t
