Self‐Supported Heterogeneous Dirhodium(II) Catalyst for Nitrene and Carbene Transfer Reactions

Abstract

The bimetallic rhodium(II) paddlewheel (Rh2A4) complex is one of the most reactive classes of rhodium catalysts, well‐renowned for the most demanding carbene‐ and nitrene‐transfer reactions. In view of its importance in modern synthetic chemistry, we herein report a facile approach for preparing a self‐supported and reusable dirhodium(II) polymer‐based heterogeneous catalyst through a reductive ligation protocol. The catalyst displays good reactivity for inter‐ and intramolecular nitrene‐ and carbene‐insertions of various olefins, and can also engage in C–H insertion of hydrocarbon derivatives, all under ambient conditions. The catalyst reusability is expected to empower the use of these precious metal catalysts at industrial scales.

Self-Supported Chiral Dirhodium Organic Frameworks Enables Efficient Asymmetric Cyclopropanation

“…N 2 adsorption−desorption isotherms indicated that both materials show low surface area of around 17 cm 2 /g, which may be ascribed to the interpenetration or stacking of coordination polymers during the synthesis of such materials (Figure 3a). 50 The pore volumes of Rh 1 -MOCP-1 and Rh 2 -MOCP-2 are 0.32 cm 2 /g and 0.38 cm 2 /g, respectively. The resulting high pore volume is most probably attributed to the aggregation of spherical particles.…”

“…These results indicated that carbon atoms C 1 and C 2 were produced during the synthesis of Rh 2 -MOCPs via Suzuki reaction between bromine groups of Rh 2 ( S -Br-NTTL) 4 and 1,4-phenylenediboronic acid or 4,4′-biphenyldiboronic acid, respectively. N 2 adsorption–desorption isotherms indicated that both materials show low surface area of around 17 cm 2 /g, which may be ascribed to the interpenetration or stacking of coordination polymers during the synthesis of such materials (Figure a) . The pore volumes of Rh 1 -MOCP-1 and Rh 2 -MOCP-2 are 0.32 cm 2 /g and 0.38 cm 2 /g, respectively.…”

“…The generality and efficiency of the dirhodium catalyst was also demonstrated in the synthesis of aziridines, which are important motifs in bioactive products and versatile intermediates for the preparation of functionlized amines. , We investigated the dirhodium catalyzed aziridination by employing styrene 2a and 2,2,2-trifluoroethyl sulfamate (H 2 NTfes) 5 as a substrate. The styrene reacted with H 2 NTfes to give aziridine product 6 with a good yield (74%) but no enantioselectivity.…”

“…26,47 Self-supported heterogeneous catalysts possess fundamental advantages compared to other immobilized catalysts with respect to high density of active sites and does not require any catalyst carrier materials. 30,48−50 Recently, Satheesh et al 50 reported the synthesis of a heterogeneous dirhodium catalyst via a self-supported approach exhibiting excellent catalytic activity in aziridination reactions.…”

“…However, heterogeneous catalysts usually exhibit inferior catalytic properties compared to their homogeneous counterparts owing to the mass transfer limitation induced by catalyst supporting materials. , In addition, the immobilized catalysts easily leach from solid carrier materials. Therefore, various efforts to the development of a facile and efficient route for the fabrication of heterogeneous catalysts are urgently needed. , Self-supported heterogeneous catalysts possess fundamental advantages compared to other immobilized catalysts with respect to high density of active sites and does not require any catalyst carrier materials. ,− Recently, Satheesh et al reported the synthesis of a heterogeneous dirhodium catalyst via a self-supported approach exhibiting excellent catalytic activity in aziridination reactions.…”