2-methylpyridine from aniline

Methylpyridines (picolines) and dimethylpyridines (lutidines) have prominent m/z 65 and m/z 66 ions in their mass spectra. Aniline can be distinguished from picolines by the m/z 78 ion in the mass spectra of picolines. If the alkyl group. R. is attached to the carbon atom adjacent to the nitrogen atom. RCN can be lost easily. Alkylpyridines are characterized by ions at m/z 65, 66, 78, 92, 106, and so forth. 

Apart from 2,4-dichlorobenzoic acid several chlorinated aromatics including chlorinated methylpyridine, benzene, methylphenol, aniline and benzoic acid occurred in the seepage water samples only in minor amounts. 2,4-dichlorobenzoic acid was also detected in the leakage water sample due to its higher abundance. 

Cyclohexanone, 2-cyclohexen-l-one, 5-hexenenitrile, and hexanenitrile are commonly observed by-products in the Beckmann rearrangement of cyclohexanone oxime. Aniline and 2-methylpyridine are also occasionally formed. An outline of the reaction scheme is shown in Figure 7. From the selectivity change with time with AIPO4 as catalyst, it was found that e-caprolactam, cyclohexanone, and... 

Two decades ago a process for the conversion of phenol into aniline was patented by Chang and Lang [5]. At 783 K and an NH3 pressure of ca 1 MPa, reasonable conversion to aniline was obtained over an H-ZSM-5 catalyst in a flow reactor. The two main by-products were diphenylamine, from the reaction of phenol with the aniline product, and 2-methylpyridine. It was suggested that the latter product was the result of a subsequent reaction of aniline. A subsequent patent... 

Boscalid (9) can be assembled starting from 2-chloronicotinic acid (17), the synthesis of which from 3-methylpyridine has been described [19]. The corresponding chloride 18 can then be reacted with the aniline 21 to obtain the desired product 9 [20]. The route from the boronic acid 19 via the 2-nitrobiphenyl 20 to 21 is the first example of the transfer of a palladium-catalyzed coupling reaction to large-scale agrochemicals synthesis (Scheme 13.3.2). 

---