Azomethinium salts

Trifluoroacetic anhydride Azomethinium salts from N-oxides s. 24,765... 

N,N-dihalogenamines 26, 269 Immoninm salts (s. a. Imidium salts) s. azomethinium salts cyclimmonium -Indan-l,3-diones (s. a. Ninhydrin)... 

Cyclic imines from cyclic azomethinium salts 1,2-Disubst. 1,2,3,4-tetrahydroisoquinolines... 

Phosphorus oxide chloride Gondensed isocyclics from vinylogous formamides via azomethinium salts... 

Without additional reagents Azomethinium salts from aminals... 

Azomethinium salts are very versatile intermediates since they present an extremely electrophilic carbon for nucleophilic attack. High yields of these salts can be obtained in one step from a-amino acids via their tert-dcsmno derivatives Ethyl N-Benzylidene-glycinate has been used for the synthesis of a-amino acids and as an acyl carbanion equivalent A new reactive formaldehyde anion equivalent is lithium methylthioformaldine, (4,5-dihydro-5-methyl-l,3,5-dithiazin-2-yllithium A convenient synthesis of 2-alkyl- and 2-aryl-l,3-benzo-dithioles, which are precursors of acyl carbanion equivalents, has recently been published . 

Ethylene derivatives from diazo compounds with rearrangement s. 18, 862 1,2-Aminoethers from azomethinium salts... 

Azomethinium betaines —, ring chlosure with — 16, 735 Azomethinium salts... 

---