Yb(OTf)₃-catalyzed Mannich reaction of imidazo[1,2-<i style="mso-bidi-font-style:normal">a</i>]pyridine and <span style="mso-ansi-language:EN-IN">pyrazolo[1,5-<i style="mso-bidi-font-style: normal">a</i>]pyrimidines </span>

290-300An efficient one-pot condensation reaction of imidazo[1,2-a]pyridine/pyrazolo[1,5-a] pyrimidines, aldehydes and acetamide has been investigated using Yb(OTf)3 as catalyst in 1,4-dioxane. The reaction furnishes good to excellent yield of 1-amidomethyl-imidazo[1,2-a]pyridines and 1-amidomethyl-pyrazolo[1,5-a]pyrimidines along with small quantities of bis(imidazo[1,2-<i style="mso-bidi-font-style: normal">a]pyridyl)methanes and bis(pyrazolo[1,5-<i style="mso-bidi-font-style: normal">a]pyrimidinyl)methanes. The product distribution is found to be dependent on the nature of imidazo[1,2-a]pyridine/pyrazolo[1,5-a]pyrimidines and aldehydes. </i