Methyl and Ring Nitrogen

Reactions of these types have been extensively utilized for synthesizing a diversity of derivatives of both types of product, and examples to demonstrate their potential are given in the following subsections. Note that the distinction between the reactions covered here and those noted in Section II,D, depending on whether the azinium salt intermediate is, or has to be, isolated, is not always clear-cut. 

The Westphal condensation between the azoniafluorene salt (219) and glyoxal (in its masked form as 2,3-dihydroxy-l,4-dioxane) or dimethylgly-oxal in the presence of triethylamine gave the lOc-azoniafluoranthene salts (220, 221), respectively (89AGE588 91JOC4858). 

Condensation of l-methyl-3,4-dihydro-)3-carboline (226) with ethyl ethoxymethyleneacetoacetate in dry methanol at room temperature for 

A quite general type of reaction is typified by those of 2-methylquinoline 

Similarly, the azepino[l,2-a]quinazoline (238) was synthesized by the reaction of dimethyl acetylenedicarboxylate with the 2-methylquinazolin-4-one (237) (72JHC1227). 

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