Layered transition metal carboxylates: efficient reusable heterogeneous catalyst for epoxidation of olefins.

Layered metal carboxylates [M(malonato)(H2O)2]n (M = Ni(II) and Mn(II)) that have a claylike structure have been synthesized hydrothermally and characterized. The interlayer separation in these layered carboxylates is comparable to that of the intercalation distance of the naturally occurring clay materials or layered double hydroxides (LDHs). In this study, we have demonstrated that, instead of intercalating the metal complex into layers of the clay or LDH, layered transition metal carboxylates, [M(malonato)(H2O)2]n, as such can be used as a recyclable heterogeneous catalyst in olefin epoxidation reaction. Metal carboxylates [M(malonato)(H2O)2]n exhibit excellent catalytic performance in olefin epoxidation reaction.