TMP–Magnesium and TMP–Zinc Bases for the Regioselective Metalation of the Cinnoline Scaffold
摘要:
A regioselective functionalization of cinnolines in positions 3 and 8 using metalations has been developed. This involves either the use of a frustrated Lewis pair consisting of BF3 center dot Et2O and TMP2Mg center dot 2LiCl or the in situ generated base TMP2Zn center dot 2MgCl(2)center dot 2LiCl. Successive metalations allow the preparation of 3,8-disubstituted cinnolines. Various functionalizations by acylation, allylation, and cross-coupling reactions with aryl halides or alkenyl iodides were carried out successfully.
A regioselective functionalization of cinnolines in positions 3 and 8 using metalations has been developed. This involves either the use of a frustrated Lewis pair consisting of BF3 center dot Et2O and TMP2Mg center dot 2LiCl or the in situ generated base TMP2Zn center dot 2MgCl(2)center dot 2LiCl. Successive metalations allow the preparation of 3,8-disubstituted cinnolines. Various functionalizations by acylation, allylation, and cross-coupling reactions with aryl halides or alkenyl iodides were carried out successfully.