Amino groups exist ubiquitously in natural products and synthetic molecules, and play key roles in a wide range of important applications. Consequently, immense effort has been devoted to the development of efficient and selective processes for the preparation of amines. [1] Among different approaches, the catalytic amination of abundant C À H bonds on the basis of a metal-mediated nitrene-insertion pathway is one of the most general and direct methods for installing nitrogen functionalities. [2] The promise of this approach as a synthetically useful methodology has been demonstrated with a number of intramolecular C À H amination processes through the combined use of Rh II 2 -based catalysts and iminoiodane nitrene sources. [2,3] Notably, Du Bois and coworkers elegantly demonstrated that N-Boc-protected sulfamides could be selectively converted into cyclic sulfamides by [Rh 2 (esp) 2 ] in combination with PhI(OAc) 2 and MgO to provide access to synthetically useful 1,3-diamines (esp = a,a,a',a'-tetramethyl-1,3-benzenedipropionate). [4] The Rh II 2based intramolecular amination was shown to be effective for both secondary and tertiary CÀH bonds with stereospecificity and high diastereoselectivity. However, the amination of strong primary CÀH bonds had yet to be demonstrated. [5] Moreover, the catalytic system was unsuitable for simple Nalkyl sulfamides, which were oxidatively degraded by the stoichiometric oxidant, PhI(OAc) 2 . [4] As stable metalloradicals, cobalt(II) complexes of porphyrins, [Co(Por)], have emerged as a new class of catalysts for CÀH amination. [6] The cobalt(II)-based metalloradical amination (MRAm) is different from the commonly studied Rh 2 system, as it can operate effectively with various azide substrates without the need for terminal oxidants and other additives. [7][8][9][10][11] To further validate the utility of C À H amination methodology based on a cobalt(II) catalyst and azides, we envisioned a general strategy for the synthesis of 1,3-diamines from monoamines through the key step of the intramolecular C À H amination of sulfamoyl azides with [Co(Por)] (Scheme 1). We report herein a cobalt(II)-based catalytic system that is highly effective for the intramolecular 1,6-CÀH amination of sulfamoyl azides to furnish six-membered cyclic sulfamides. Not only excellent regioselectivity, but also high diastereoselectivity and stereospecificity were observed with the catalytic system. The cobalt(II)-catalyzed amination is operationally simple, as it proceeds under neutral and nonoxidative conditions without the need for other reagents, and N 2 is the only byproduct. Consequently, the degree of functional-group tolerance is high, and the reaction can be applied to substrates with various substituents, such as oxidizable amide and sulfide groups. An important feature of this catalytic system is the effective amination of strong primary C À H bonds, as well as secondary and tertiary C À H bonds.A wide range of sulfamoyl azides 2 were conveniently prepared from the corresponding amines 1 on the ...

Das 12‐fach verknüpfte Metall‐organische Gerüst (MOF) MMPF‐3 wurde ausgehend von einem Cobalt(II)‐Porphyrin erzeugt und enthält dieselben polyedrischen supramolekularen Bausteine wie das prototypische fcu‐MOF‐1. Die Nanohohlräume von MMPF‐3 verfügen jeweils über achtzehn katalytisch aktive Cobaltzentren, und die hohe Dichte von ca. fünf Cobaltzentren pro nm3 sorgt dafür, dass MMPF‐3 anderen MOFs in der katalytischen Epoxidierung von trans‐Stilben überlegen ist.

Biomimetic metal-organic frameworks have attracted great attention as they can be used as bio-inspired models, allowing us to gain important insights into how large biological molecules function as catalysts.I nt his work, we report the synthesis and utilization of such am etal-metalloporphyrin framework (MMPF) that is constructed from ac ustomdesigned ligand as an efficient halogen bond donor catalyst for Diels-Alder reactions under ambient conditions.T he implementation of fabricated halogen bonding capsule as binding pocket with high-density CÀBr bonds enabled the use of halogen bonding to facilitate organic transformations in their three-dimensional cavities.T hrough combined experimental and computational studies,weshowed that the substrate molecules diffuse through the pores of the MMPF,establishing ahost-guest system via the CÀBr•••p interaction. The formation of halogen bonds is ap lausible explanation for the observed boosted catalytic efficiency in Diels-Alder reactions.M oreover,t he unique capability of MMPF highlights new opportunities in using artificial non-covalent binding pockets as highly tunable and selective catalytic materials. Scheme 1. a) Halogen-bondformation in PDB 3DV3, 3DY7 and 3KXH between the backbone carbonyl oxygen and the halogen atom. b) The formation of the sigma hole:T he covalent bond (CÀX) between the halogen (s-bond, green) pairs and the carbon atom, an electron from the carbon atom with one from the halogen atom. c) 5,15-bis(3,5dicarboxyphenyl)-10,20-bis(2,6-dibromophenyl)porphyrin (H 4 dcdbp) ligand in this work, ahigh density of halogen-donor sites in the MMPF network and the microscope images of Mg-MMPF-3.

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