Highly efficient synthesis of 3-amino-/alkylthio-cyclobut-2-en-1-ones based on the cyclization of acyl ketene dithioacetals.

Regiodivergent heterocyclization: a strategy for the synthesis of substituted pyrroles and furans using α-formyl ketene dithioacetals as common precursors.

The selective construction of a diverse array of five-membered aromatic heterocycles from common starting materials is an attractive and challenging task. We report here that 5-alkylthio-pyrroles, 4-alkylthiocarbonyl-pyrroles and 2-alkylthio-4-tosyl-furans can be prepared, selectively, in a single operation using the readily available α-formyl ketene dithioacetals as common precursors, through ...

A convenient base-mediated synthesis of 3-aryol-4-methyl (or benzyl)-2-methylthio furans from α-oxo ketene dithioacetals and propargyl alcohols via domino coupling/annulations.

A convenient base-mediated strategy to synthesize 3-aryol-4-methyl (or benzyl)-2-methylthio furans 2 (trisubstituted furans) has been developed through the domino coupling/annulations between available α-oxo ketene dithioacetals 1 and propargyl alcohols. In this strategy, these types of bases play an important role in driving the domino coupling reaction of propargyl alcohols and further intram...

Aerobic copper-catalyzed oxidative [6C+1C] annulation: an efficient route to seven-membered carbocycles.

It has been revealed for the first time that co-promoted by CuCl and NaH in the presence of molecular oxygen (air), the reaction of dicinnamoyl ketene dithioacetals as the acyclic C6 synthons with ethyl cyanoacetate gives functionalized seven-membered carbocycles. A mechanism is proposed involving a tandem Michael addition-intramolecular radical cyclization-benzyl C(sp(3))-H bond oxidation.

Aldol type Condensation Reactions of Acyl Ketene Dithioacetals

Iron-Catalyzed Oxidative C-H Functionalization of Internal Olefins for the Synthesis of Tetrasubstituted Furans.

Tetrasubstituted furans were efficiently synthesized from Fe(OAc)2-catalyzed C-H/C-H cross-dehydrogenative-coupling (CDC) reactions of activated carbonyl methylenes with S,S-functionalized internal olefins, that is, α-oxo ketene dithioacetals and analogues, under oxidative conditions. β-Ketoesters, 1,3-dicarbonyls, β-keto nitrile, and amide derivatives were used as the coupling partners. The re...