Hd. Stachel et K. Zeitler, ALPHA-THIOTETRONIC ACIDS .1. SYNTHESIS AN D PROPERTIES OF GAMMA-ALKYLIDENE ALPHA-THIOTETRONIC ACIDS, Archiv der pharmazie, 328(2), 1995, pp. 99-107
We report on the synthesis of the alkylidene alpha-thiotetronic acids
11 and 12a and a variety of their derivatives, starting with 2,3-dimet
hoxysuccinic thioanhydride (4) or diethyl 3-thioxoglutarate. The rhodi
um(II) -catalysed decomposition of the diazoketone 26 furnishes the re
ductone 12p and the aminoreductone 12r with the thietanone 27 as one o
f the by-products.