No abstract

A series of new N-(pytidylmethyl)azinium salts have been synthesized from 2, 4, 6.tnphenylpyrylium tetrafluoroborate. Generation of azinium N-ylides i n the presence of base, has been proved by reactions with electrophiles. such as carbon disulphide, phenyl isothiocyanate and with acetylene dipolarophiles. Azinium N-ylides are highly interesting compounds due to their reactivity as organic dipoles, as well as to their biological properties and applications.'-' Usually. simple electron-attracting groups, such as 12426 J. AGE?JAS et al. RESULTS AND DISCUSSION Synthesis. We had previously described6a,b that pyridinium-N-(2'-pyridyl)aminides can be prepared from 1-(2',4'-dinitrophenyl)pyridinium halides 4 (Zincke salts).6c However, adapting this method to the synthesis of the N-ylides 1 and 2 (Route A, Scheme I) proved to be difficult even in high boiling alcohols,' and yields of salts 9 were not higher than 18%. As an alternative, we adapted a procedure described by KatritzJcyga to produce, in two steps, the reqmred salts 9 (Route B, Scheme I). 3a Z-pyndyl 3b Spyridyl 3c 4-pyndyl Scheme 1