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  • Grade: pharmaceutical grade

    Factory Location: china

    Main Sales Markets: North America,Central/South America,Western Europe,Eastern Europe,Australasia,Eastern Europe,Australasia,Asia,Middle East,Africa

  • Packaging Information: 1kg/bag

  • Sample Provided: no

    Payment Terms: Bank transfer

    Pyridine N-oxide is a stable class of organic compounds that can be used as a starting material for the synthesis of pyridine derivatives. The idea of using abundant and readily available olefins as alkylating reagents to convert pyridine N-oxide to ortho-alkylsubstituted pyridine is very attractive. However, there are only a few such reports and are only applicable to electron-deficient olefins. For example, perfluoropropene reacts with pyridine N-oxide to obtain tetrafluoroethyl-substituted pyridine by 1,3-dipole cycloaddition and carbonyl fluoride elimination (Figure 1a, J. Org. Chem. 1968, 33, 3343–3344; MendeleevCommChemicalbookun.2006,16,161–163)。 Although pyridine N-oxides contain polar N–O bonds, their 1,3-dipole activity is low for cycloaddition reactions, possibly due to the simultaneous disruption of the aromatization of both substrates in the reaction. One solution to this problem is to use photocatalytic radical species generated by simple alkenes as alkylation components of pyridine N-oxides. Because such cationic radicals have sufficient electrophilicity, they can be coupled with pyridine N- oxide to form radical intermediates, and then after intramolecular ortho-addition and carbonyl compound elimination, ortho-substituted pyridine products can be obtained
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