Synthesis of 3-iodobenzo[b]thiophenes via iodocyclization/etherification reaction sequence

Iodocyclization of Propargyl Alcohols: Highly Facile Approach to Hetero/Carbocyclic Iodides

“…A simple thiomethyl ether 126 was subjected to iodocyclization with iodine and alcohol (ROH) in acetonitrile at r.t. (Scheme ). In contrast to the above method (Scheme ), 2‐alkoxy‐3‐iodo‐thiophene derivatives ( 127a – 127l ) were obtained here in good yields . Alcohol acted as a nucleophile and substituted the oxonium ion on the 2‐position of thiophene and yielded 127 .…”

“…Sulfur and selenium‐containing compounds serve as very useful heterocyclic cores for drug leads and biologically active compounds and provide useful properties in the development of novel materials . Synthetic methods for the preparation of iodothiophene, iodobenzothiophene (Scheme –Scheme ) and iodoselenophene (Scheme ) will be discussed in this section.…”

Combinatorial Chemistry Online Volume 17, Issue 2, February 2015

“…An efficient method has been developed for the synthesis of benzo[b]thiophene core structure using a two-step, multicomponent reaction resulting in favorable yields [5]. This convergent reaction proceeds at room temperature thus eliminating the harsh reaction conditions usually associated with the synthesis of benzo[b]thiophene ring structures.…”

Synthesis of 2‐Substituted Benzothio(seleno)phenes and Indoles via Ag‐Catalyzed Cyclization/Demethylation of 2‐Alkynylthio(seleno)anisoles and 2‐Alkynyldimethylanilines

“…has been proven to be one of the most efficient and valuable ways [6a–k,8a–e] (Scheme 1). For example, by employing this methodology, Flynn's, [6a] Larock's, [6b–e,8a–e] Sanz's, [6i] Wu's, [6f] Balova's [8i] and Kesharwani's [6j,k] groups reported a series of 2,3‐disubstituted benzothio(seleno)phenes or indoles, respectively. Ingleson and co‐workers have described the preparation of C3‐borylated benzofurans and benzothiophenes by using BCl 3 as an electrophilic partner [9] .…”