The first direct synthesis of β-unsubstituted meso- decamethylcalix[5]pyrrole

• Luis Chacón-García,
• Lizbeth Chávez,
• Denisse R. Cacho and
• Josue Altamirano-Hernández

Beilstein J. Org. Chem. 2009, 5, No. 2, doi:10.3762/bjoc.5.2

• The first direct synthesis of β-unsubstituted meso-decamethylcalix[5]pyrrole from pyrrole and acetone, with moderate yield, is described. The results showed that a bismuth salt was necessary to obtain calix[5]pyrrole, with the best results obtained using Bi(NO3)3. Keywords: bismuth; calix[5]pyrrole

• , all of these Lewis acids catalyzed the reaction to give 1 and/or 4 in amounts ranging from traces to moderate yields. Bismuth salts also produced 3. The results showed that a bismuth salt was necessary to obtain calix[5]pyrrole 2, with the best results being obtained with Bi(NO3)3. The advantages of