Copper‐Catalyzed Electrophilic Amination of Heteroarenes and Arenes by C?H Zincation

Direct amination of heteroarenes and arenes has been achieved in a one‐pot C H zincation/copper‐catalyzed electrophilic amination procedure. This amination method provides an efficient and rapid approach to access a diverse range of heteroaromatic and aromatic amines including those previously inaccessible using C H amination methods. The mild reaction conditions and good functional‐group compatibility demonstrate its great potential for the synthesis of important and complex amines.     

Direct Synthesis of 1,4‐Diols from Alkenes by Iron‐Catalyzed Aerobic Hydration and C?H Hydroxylation

Various 1,4‐diols are easily accessible from alkenes through iron‐catalyzed aerobic hydration. The reaction system consists of a user‐friendly iron phthalocyanine complex, sodium borohydride, and molecular oxygen. Furthermore, the effect of additional ligands on the iron complex was examined for a model reaction. The second hydroxy group is installed by direct C(sp³) H oxygenation, which is based on a [1,5] hydrogen shift process of a transient alkoxy radical that is formed by formal hydration of the olefin.     

Iron‐Catalyzed Chemoselective ortho Arylation of Aryl Imines by Directed C?H Bond Activation

No Fe‐ar : Iron catalyzes an imine‐directed C? H bond activation to introduce an ortho‐aryl group to an acetophenone‐derived imine using a diarylzinc reagent (see scheme), whereas palladium catalyzes the conventional substitution reaction . The title reaction features mild and selective C? H bond activation in the presence of aryl bromide, chloride, or sulfonate groups, and 1,2‐dichloroisobutane is essential to achieve such selectivity.

     

Iron‐Catalyzed Chemoselective ortho Arylation of Aryl Imines by Directed C?H Bond Activation

Naheliegende Alternative : Eine eisenkatalysierte Imin‐gesteuerte C‐H‐Aktivierung mit einem Diarylzinkreagens führt eine Arylgruppe in ortho‐Stellung an einem von Acetophenon abgeleiteten Imin ein (siehe Schema); mit einem Palladiumkatalysator tritt dagegen eine gewöhnliche Substitution auf. Die Titelreaktion ist eine milde C‐H‐Aktivierung, die in Gegenwart von 1,2‐Dichlorisobutan mit Arylbromiden, ‐chloriden oder ‐sulfonaten selektiv verläuft.

     

Synthesis of 1,3‐Diamines Through Rhodium‐Catalyzed C?H Insertion

A grand opening : N‐Boc‐N‐alkylsulfamides are effective substrates for the title transformation. Oxidative cyclization is highly chemoselective as well as being both stereospecific and diastereoselective. With the advent of new protocols that facilitate ring opening of the six‐membered‐ring heterocyclic products, access to differentially protected 1,3‐diamines has been made possible (see scheme).

     

Synthesis of 1,3‐Diamines Through Rhodium‐Catalyzed C?H Insertion

Schließen und öffnen : N‐Boc‐N‐alkylsulfamide sind geeignete Substrate für die Titelreaktion. Die oxidative Cyclisierung im ersten Schritt ist hoch chemoselektiv sowie stereospezifisch und diastereoselektiv. Mit neuen Verfahren zur Öffnung der dabei erhaltenen Sechsringheterocyclen werden unterschiedlich geschützte 1,3‐Diamine zugänglich (siehe Schema).

     

Synthesis of Imides by Palladium‐Catalyzed C?H Functionalization of Aldehydes with Secondary Amides

An efficient palladium‐catalyzed C? H functionalization of aldehydes with various N‐substituted N‐heteroarene‐2‐carboxamides has been developed for the synthesis of secondary imides. The reaction tolerates various functionalities, such as methoxy, fluoro, chloro, and bromo groups. A tentative radical mechanism for a Pd^II/Pd^IV catalytic cycle is proposed.