Rh‐Catalyzed Direct Carboxylation of Alkenyl C−H Bonds of Alkenylpyrazoles
Takanobu Saitou, Yushu Jin, Kotaro Isobe, Takuya Suga, Jun Takaya, Nobuharu Iwasawa
Abstract
Abstract The Rh‐catalyzed direct carboxylation of alkenyl C−H bonds was achieved by using pyrazole as a removable directing group. In the presence of 5 mol% RhCl 3 ⋅ 3H 2 O, 6 mol% P(Mes) 3 , and 2 equiv. of AlMe 2 (OMe), the alkenyl C−H bond of various alkenylpyrazoles was directly carboxylated in good yields under CO 2 atmosphere. Furthermore, several useful transformations of the pyrazole moiety of the product were achieved to afford synthetically useful carboxylic acid derivatives in good yields.
Topics & Concepts
CarboxylationMoietyChemistryCatalysisPyrazoleMedicinal chemistryCarboxylic acidStereochemistryOrganic chemistryCarbon dioxide utilization in catalysisCatalytic C–H Functionalization MethodsCatalytic Alkyne Reactions