Journal Article

A Convenient One-Pot Synthesis of a Sterically Demanding Aniline from Aryllithium Using Trimethylsilyl Azide, Conversion to Iβ/I-Diketimines and Synthesis of a Iβ/I-Diketiminate Magnesium Hydride Complex

Bourne, Connor, Cordes, David B, Stasch, Andreas, Grebogi, Mateus, McKay, Aidan P, Demidov, Nikita

2023

Overview

This work reports the one-pot synthesis of sterically demanding aniline derivatives from aryllithium species utilising trimethylsilyl azide to introduce amine functionalities and conversions to new examples of a common N,N′-chelating ligand system. The reaction of TripLi (Trip = 2,4,6-iPr[sub.3]-C[sub.6]H[sub.2]) with trimethylsilyl azide afforded the silyltriazene TripN[sub.2]N(SiMe[sub.3])[sub.2] in situ, which readily reacts with methanol under dinitrogen elimination to the aniline TripNH[sub.2] in good yield. The reaction pathways and by-products of the system have been studied. The extension of this reaction to a much more sterically demanding terphenyl system suggested that TerLi (Ter = 2,6-Trip[sub.2]-C[sub.6]H[sub.3]) slowly reacted with trimethylsilyl azide to form a silyl(terphenyl)triazenide lithium complex in situ, predominantly underwent nitrogen loss to TerN(SiMe[sub.3])Li in parallel, which afforded TerN(SiMe[sub.3])H after workup, and can be deprotected under acidic conditions to form the aniline TerNH[sub.2]. TripNH[sub.2] was furthermore converted to the sterically demanding β-diketimines [sup.RTrip]nacnacH (=HCRCN(Trip)[sub.2]H), with R = Me, Et and iPr, in one-pot procedures from the corresponding 1,3-diketones. The bulkiest proligand was employed to synthesise the magnesium hydride complex [([sup.iPrTrip]nacnac)MgH[sub.2]], which shows a distorted dimeric structure caused by the substituents of the sterically demanding ligand moieties.

• Publisher: MDPI AG
• Subject: Aniline / Chemical tests and reagents