Regioselective Synthesis of
Functionalized 3-(Methylthio)phenols by the First Formal [3+3] Cyclocondensations
of 1,3-Bis(trimethylsilyloxy)-1,3-butadienes with 1,1-Bis(methylthio)-1-en-3-ones
The [3+3] cyclocondensation of 1,3-bis(silyl enol ethers) with 1,1-bis(methylthio)-1-en-3-ones results in the regioselective formation of 3-(methylthio)phenols. The products represent useful synthetic building blocks, which are not readily available by other methods.
Regioselective synthesis of 3-(methylthio)phenols by formal [3+3]-cyclocondensations of 3-oxo-bis(methylthio)ketenacetals with 1,3-bis(trimethylsilyloxy)-1,3-butadienes and 1,3-dicarbonyl dianions
The cyclization of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with 3-oxo-bis(methylthio)ketenacetals afforded 3-(methylthio)phenols containing an acyl or ester substituent located at position 2. The cyclization of free 1,3-dicarbonyl dianions with 3-oxo-bis(methylthio)ketenacetals resulted in the formation of regioisomeric products containing an acyl group located at position 6.