Carboxylation of Acetylene without Salt Waste: Green Synthesis of C Chemicals Enabled by a CO -Pressure Induced Acidity Switch.

The inherent formation of salt waste in C-H carboxylations is a key obstacle precluding the utilization of CO as C building block in the industrial synthesis of base chemicals. This challenge is addressed in a circular process for the production of the C base chemical dimethyl succinate from CO and acetylene. At moderate CO pressures, acetylene is doubly carboxylated in the presence of cesium carbonate.

Iron-Catalyzed Decarboxylation of Trifluoroacetate and Its Application to the Synthesis of Trifluoromethyl Thioethers.

Nucleophilic CF3 has been generated by decarboxylation of potassium trifluoroacetate, arguably the most easy-to-handle, inexpensive, and sustainable source of trifluoromethyl groups. Simple iron(II) chloride catalyzes the decarboxylation as well as a subsequent trifluoromethylation of organothiocyanates, resulting in a straightforward synthesis of trifluoromethyl thioethers. The KCN byproduct is absorbed by iron(II) with formation of nontoxic potassium hexacyanoferrate.