Simple Access to 2‐Arylbenzo[b]tellurophenes

Abstract

AbstractArguably, the simplest way for the preparation of benzo[b]tellurophenes has been elaborated. Cyclization of o‐haloarylalkynes in the presence of Te‐NaOH‐DMSO triad occurs by simple mixing of starting materials and heating overnight without the need for dry and inert atmosphere and provides the corresponding benzo[b]tellurophenes in up to 90 % GC‐yield. Catalytic telluration of aryl iodide substrates extends the applicability of the developed cyclization cascade to substrates that are not suitable for the direct SNAr/5‐endo‐dig cyclization approach. Successful SEAr in the third position of benzo[b]tellurophene provides a synthetic intermediate for the preparation of Te analogues of selective estrogen receptor modulator (SERM) raloxifene.