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

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