No abstract

An operationally simple and practical protocol for the synthesis of (E)-α-halo vinyl sulfides has been achieved via a highly regio- and stereoselective hydrohalogenation of alkynyl thioethers using lithium halides in HOAc or propionic acid at room temperature. It permits the formation of (E)-α-chloro and (E)-α-bromo vinyl sulfides in satisfactory yields with good to excellent stereoselectivities. Moreover, this work results in a new method for the assembly of stereodefined (E)- or (Z)-trisubstituted alkenes featuring the first coupling of the C-X bond of (E)-α-halo vinyl sulfides followed by a subsequent Ni-catalyzed coupling of the C-S bond with Grignard reagents.

Using cheap and readily accessible CuCl as the catalyst, an operationally simple and efficient method for the synthesis of 3,5-disubstituted oxazolones has been realized by the cyclization of N-alkynyl tert-butyl carbamates. The reaction proceeds under mild reaction conditions and shows good functional group compatibility.

A highly regio‐ and stereoselective hydrohalogenation of alkynyl thioethers leads to (E)‐α‐halo vinyl sulfides (II).

A simple and efficient method for the synthesis of 3,5‐disubstituted oxazolones (II) is developed.