Alkali–Amide-Catalyzed One-Pot Aminoallylation of Aldehydes with Allylbenzenes

Abstract

The deprotonation of allylbenzene was successfully demonstrated with a catalytic alkali amide base (NaN(SiMe 3 ) 2 ). The deprotonated allyl anion could be trapped by in situ generated N-(trimethylsilyl) aldimines to provide value-added homoallylic amines (39 examples, 68−98% yields) in a one-pot manner with excellent liner selectivity. Compared with the previously reported method for the synthesis of homoallylic amines, this method does not need to use the preinstalled protection groups on the imines, which need to be removed after the reaction to obtain the N−H free homoallylic amine derivatives.

A Tandem Madelung Indole Synthesis Mediated by a LiN(SiMe3)2/CsF System

“…These mixed bases provided an alternative route to reversibly deprotonate benzylic C–H bonds. Successful examples include one-pot aminobenzylation of aldehydes with toluene (Scheme a), tandem synthesis of indole from 2-fluorotoluene and nitriles (Scheme b), and many others . Efficient benzylic C–H bond deprotonation systems were also reported by others, such as TMAF/N­(TMS) 3 by Kondo and Shigeno, LDA by Guan, KCH 2 TMS by Kobayashi, n -BuLi/LiK­(OCH 2 CH 2 NMe 2 ) 2 /Mg­(OCH 2 CH 2 OEt) 2 by Screttas, and others .…”

Synthesis of Homoallylamines Enabled by Cobalt or Palladium Catalyzed Allylic Substitution of Azaarylmethylamines

“…We are interested in alkali amide mediated deprotonative functionalizations of weakly acidic C(sp) 3 –H bonds. Successful examples developed by us include one-pot aminoalkylations with weakly acidic substrate, such as toluene, allylarenes, azaarylmethylamines, and many others . More recently, these weakly acidic substrates were employed to synthesize heterocycles .…”

“…Recently, a variety of allylic alkylations of weakly acidic C(sp) 3 −H bonds have been developed with substrates including 2-methylpyridines, 20 alkyl sulfones, 21 methyl azaarenes, 22 diarylmethanes, 23 toluene derivatives, 24 ful examples developed by us include one-pot aminoalkylations with weakly acidic substrate, such as toluene, 25 allylarenes, 26 azaarylmethylamines, 27 and many others. 28 More recently, these weakly acidic substrates were employed to synthesize heterocycles.…”

Silylation of Allylic C(sp3)–H Bonds Enabled by the Catalytic Generation of Allylpotassium Complexes

“…This process has been fruitfully exploited in the catalytic silylation of unactivated C­(sp 2 )–H 16 and benzylic C­(sp 3 ) –H bonds . We herein disclose a novel and operationally simple approach toward linear allylsilanes that capitalizes on the facile catalytic generation of nucleophilic allylpotassium species directly from 1- or 2-alkenes (Scheme C) …”