An efficient stereoselective synthesis of difluoromethylated alkenes in a microreactor

Synthetic utility of microreactors and highly stereoselective isomerization (>99:<1) of terminal difluoromethylated alkenes to (E)-difluoromethylated alkenes with TBAF in DMF, are described.     

Trifluoromethylation of Allenes: An Expedient Access to α-Trifluoromethylated Enones at Room Temperature

A silver(I) catalyzed regioselective trifluoromethylation of allenes using Langlois's salt (NaOSOCF₃) is demonstrated. This transformation enables direct expedient access to α-trifluoromethylated acroleins, which are valuable synthons for a number of pharmaceuticals and agrochemicals containing vinyl-CF₃ moieties. Versatility of this trifluoromethylation method has been established with good yield and excellent regioselectivity. Preliminary experiments and computational studies were carried out to elucidate the mechanistic insight of this protocol.     

KI as iodine source for the synthesis of E-iodovinyl sulfones via metal-free iodosulfonylation of terminal alkynes

The E-selective iodosulfonylation of terminal alkynes has been achieved by employing sulfonyl hydrazines and potassium iodide as sulfonyl and iodine sources, respectively. Besides using simple and cheap reactants, the present method requires no metal catalyst and proceeds well at room temperature. A broad array of iodovinyl sulfones have been efficiently synthesized via the alkyne difunctionalization in the presence of benzoic peroxyanhydride (BPO).