TTF II. Hydrolysis of dimethyl 1,3-dithiole-2-thione-4,5-dicarboxylate
SyntheticPage 278
DOI:
Submitted: June 5, 2008, published: June 5, 2008
Authors
Nikola Paul Chmel (n.chmel@warwick.ac.uk)
A contribution from
Chemicals
dimethyl 1,3-dithiole-2-thione-4,5-dicarboxylate (see [[277|Page 277]]),
concentrated hydrochloric acid (Fisher),
glacial acetic acid (Fisher)
concentrated hydrochloric acid (Fisher),
glacial acetic acid (Fisher)
Procedure
Mixture of dimethyl 1,3-dithiole-2-thione-4,5-dicarboxylate (20g, 0.079mol), concentrated HCl (86ml), glacial acetic acid (40ml) in water (120ml) was refluxed at 170°C until all substrate dissolved (approx. 2 h). Product precipitated upon cooling (water/ice bath), filtered without washing, dried in vacuo. Filtrate was evaporated to dryness to obtain second crop. Total yield 17.8g
Author Comments
Has been performed several times with similar yields. Product was used immediately in subsequent reaction, and this may be a good idea as it is slightly air sensitive.
Data
1H NMR (400MHz, Acetone-d6, 298K) 8.32 (s, COOH)
Lead Reference
L.R. Melby, H.D. Hartzler, W.A. Sheppard, J.Org. Chem. Vol. 39, No. 16, (1974) 2456-2458