2-Pyridinealdoxime

As described in U.S. Patent 3,123,613, the preparation of the intermediate product, 2-pyridineaidoxime methomethylsulfate, Is as follows. 1 kg of 2-pyridinealdoxime is dissolved in 6 liters of acetone and filtered until clear. 2 kg (2 equivalents) of freshly distilled dimethyl sulfate are added and the solution mixed. In about 30 minutes crystals start to appear, after which a cooling bath is used to keep the temperature at about 30° to 35°C until the reaction is nearly complete (about 2 hours). 

S. Ozaki, H. Nakagawa, K. Fukuda, S. Asakura, H. Kiuchi, T. Shigemori, and S. Takahashi, Re-activation of an amperometric organophosphate pesticide biosensor by 2-pyridinealdoxime methochloride. Sens. 

A recent addition to this field is the polymer-supported di(2-pyridyl)-methylamine-palladium dichloride complex covalently attached to a styrene-alt-maleic acid anhydride copolymer. Turnover numbers as high as 105 were reported and a couple of microwave-heated Suzuki-Miyaura reactions could be performed in neat water [134], 2-Pyridinealdoxime-based Pd(II)-... 

In conclusion, a MINDO/3 study on the pyridine-2-aldoximes and related derivatives revealed that the syn-2 -pyridinealdoxime is more stable than the corresponding anti isomer. The difference in the isomers is reverted when the corresponding anions are formed. In agreement with the experimental observations, in the case of N-methylated forms, the anti isomer is more stable than the syn form and based on this, it was concluded that the anti-2-PAM is the active form of this well-known drug. It was found that in all of the above oximes, the oxime portion is near perpendicular to the ring of the pyridine except in the anions of the pyridine-2-aldoximes in which a coplanar structure is the most stable. 

FIGURE 72.28 Imidazole aldoximes from a study in the United FIGURE 72.31 3-Hydroxy-2-pyridinealdoxime moiety containing States (Sit et al., 2011). reactivators with butane/pentane Unker. (Mercey el al., 2011). 

FIGURE 72.29 Reactivators derived from praUdoxime and edro- FIGURE 72.32 3-Hydroxy-2-pyridinealdoxime moiety containing... 

FIGURE 72.33 Reactivators with 3-hydroxy-2-pyridinealdoxime moiety and variable PSL (Renou et al, 2013). 

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