Grindstone Telescopic Approach for Pyrrolodiazepines Through Pictet‐Spengler‐Type Reaction and Solvent‐Free Synthesis of Quinazolines
Maitreyee Panda, Anirban Bera, Dibas Dandapat, Paritosh Barik, Shubhendu Dhara, Mohammed Ikbal, Kuheli Pramanik, Smritimoy Pramanik, Shubhankar Samanta
Abstract
Abstract Hypervalent iodine activated Pictet‐Spengler‐type telescoping strategy under grindstone technology has been reported for the first time to construct pyrrolodiazepine with minimum E‐factor. The same hypervalent iodine is also applicable to the synthesis of quinazoline cores in moderate to excellent yields under neat conditions. This greener approach for N ‐centered heterocycles is superior compare to the traditional methods due to its shorter reaction time, eco‐friendly conditions, reduced cost, lower energy consumption, higher yields of desired products, and broader substrate scope. The scale‐up experiment for the Pictet–Spengler‐type reaction and the extension of protocol to the Bischler–Napieralski reaction give a new feather of the sustainable chemistry.