1.3- Dithiolylium salts reaction with amines

The reaction of 2-methylsulfanyl-1,3-dithiolylium salts (305) with secondary amines results in the formation of the corresponding 2-amino-dithiolylium salts (306) (Equation (61)) <64JOC2877>. 

Amino- and imino-dithioles are available in some cases by ring syntheses, but the most general methods involve the reaction of an amine with a 3(or 5)-chloro-l,2-dithiolylium salt or. a chloro-l,2-dithiole respectively (80AHC(27)l5l), and protonation or alkylation of these gives aminodithiolylium salts. 

Many tetrathiafulvalenes have been prepared by deprotonation of 1,3-dithiolylium salts with tertiary amines (76S489, 80AHC(27)151). In this reaction, the intermediate resonance... 

Often l,2-dithiole-3-thiones are formed as by-products in reactions involving 1,2-dithiolylium salts, probably by reaction of the 1,2-dithiolylium ion with elemental sulfur from decomposition of the dithiolylium salt. With tertiary amines, 1,2-dithiolylium salts give not tetrathiafulvalenes but l,2-dithiole-3-thiones6 (e.g., la - 2). 

With aryl amines the reaction of 3-methylthio-1,2-dithiolylium salts (11) not substituted in the 5-position gives l,2-dithiole-3-thiones arylated in the 5-position13 (12). 

The synthesis of enamino-thioketones has been pursued mainly by the groups of Quiniou and Usov. " Traditional methods employed include reaction of P4S10 with enamino-ketones, reaction of amines with 1,2-dithiolylium salts, and transamination of enamino-thioketones, > which was used to prepare the previously unknown simple compound (18). Access to thioamide vinylogues has also been achieved through the reaction of a monothio-/3-diketone with ammonia, and, for 3-amino-2-arylindene-l-thiones (19), by reaction of enamino-imines with P4S10 or sodium hydrosulphide or by reaction of 1-imino-2-aryl-2-alkyloxyindene tetrafluoroborates with sodium hydrosulphide. ... 

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