The Synthesis and the Characterization of the Monomethyl- And the Dimethyl-Quinolines

All 7 monomethyl- and all 21 dimethyl-quinolines were synthesized by unambiguous methods and those solid above room temperature were purified to their maximum melting points. The picrates, styphnates, and trinitro-m-cresolates of each quinoline were prepared and their properties recorded. The picrates in particular were purified to their ultimate melting points. Incidentally, 7-ethyl-quinoline and a number of trimethyl-quinolines were also prepared. It is concluded that the melting points previously given in the literature for most of the picrates are of little use for identification purposes.