Rh-Catalyzed Direct Carboxylation of Alkenyl C-H Bonds of Alkenylpyrazoles.

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  ⋅ 3H O, 6 mol% P(Mes) , and 2 equiv. of AlMe (OMe), the alkenyl C-H bond of various alkenylpyrazoles was directly carboxylated in good yields under CO atmosphere.

Characterization of water in hydrated Bombyx mori silk fibroin fiber and films by H NMR relaxation and C solid state NMR.

Unlabelled: The mechanical properties of Bombyx mori silk fibroin (SF), such as elasticity and tensile strength, change remarkably upon hydration. However, the microscopic interaction with water is not currently well understood on a molecular level. In this work, the dynamics of water molecules interacting with SF was studied by H solution NMR relaxation and exchange measurements.