Reactions of Alkyl- and Aryl-1,8-Naphthyridines

Only reactions specific to the alkyl or aryl groups in such 1,5-naphthyridines are illustrated in the following examples. 

2-Methyl-1,5-naphthyridine (40) with ethyl picolinate gave 2- (picolinoyl-methyl)-l,5-naphthyridine (41) [reactants, THF, N2, —78°C (Me3Si) 2NK/ PhMeJ, 10 min then —78°C, 1 h 95%] several analogs likewise.268 

2-Methyl-1,5-naphthyridine 1,5-dioxide (42, R=H) gave 2-bromomethyl-l, 5-naphthyridine 1,5-dioxide (42, R=Br) (dioxane dibromide 81% for further details, see original).290 See also Section 3.1.1. 

5-Naphthyridine methiodide (43) underwent oxidative imination to 1-methyl-l,5-naphthyridin-2 (1 //)-imine hydriodide (44), accompanied by partial 

3-Ethyl-l,5-naphthyridine (46) gave l,5-naphthyridine-3-carboxylic acid (47) (substrate, H20, 70°C KMn04J, during 1 h then 70°C, 30 min 35%, allowing for some recovered substrate).155 

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