A base-promoted synthesis of 3,4-dihydro-2(1<i>H</i>)-quinazolinones

Abstract A convenient and concise base-promoted synthesis of 3,4-dihydro-2(1 H )-quinazolinones and multi-membered cyclic ureas has been developed. In the presence of t BuOK, a variety of 3,4-dihydro-2(1 H )-quinazolinones as well as the N -arylated five-, six- and nine-membered cyclic ureas were readily synthesized under mild conditions. This method offers an alternative synthesis toolkit towards cyclic ureas.