Diastereoselectively Complementary C–H Functionalization Enables Access to Structurally and Stereochemically Diverse 2,6-Substituted Piperidines
作者:Gang Wang、Ying Mao、Lei Liu
DOI:10.1021/acs.orglett.6b03372
日期:2016.12.16
The preparation of 2,6-substituted piperidine derivatives through diastereoselective C–H functionalization of corresponding nitrogen heterocycles represents an appealing protocol and yet remains a formidable challenge. Here, we describe a stereochemically complementary oxidative C–H functionalization of N-carbamoyl tetrahydropyridines with a wide variety of building blocks, providing either the cis-
A Direct Synthesis of Allenes by a Traceless Petasis Reaction
作者:Devon A. Mundal、Kelly E. Lutz、Regan J. Thomson
DOI:10.1021/ja301489n
日期:2012.4.4
A one-pot synthesis of allenes by the 2-nitrobenzenesulfonylhydrazide-mediated coupling of hydroxyaldehydes or ketones with alkynyl trifluoroborate salts is reported. This mild process involves in situ formation of a sulfonylhydrazone that reacts with alkynyl trifluoroborates to generate a transient propargylic hydrazide species. Decomposition of this unstable hydrazide via an intermediate monoalkyldiazine
Enantioselective Organocatalytic Multicomponent Synthesis of 2,6-Diazabicyclo[2.2.2]octanones
作者:Maria del Mar Sanchez Duque、Olivier Baslé、Yves Génisson、Jean-Christophe Plaquevent、Xavier Bugaut、Thierry Constantieux、Jean Rodriguez
DOI:10.1002/anie.201306656
日期:2013.12.23
compounds: The title reaction of β‐ketoamides, acrolein, and aminophenols, catalyzed by a bifunctional thiourea‐tertiary amine organocatalyst, enables the preparation of an enantioenriched diazabicyclo[2.2.2]octanone (2,6‐DABCO) scaffold. The chemoselective reaction sequence installs five new bonds and three stereocenters, two of which are contiguous tetrasubstituted centers, with excellent yields and high
Synthesis of 5-alkynyl-2,2,6-trimethyl-1,3-dioxin-4-ones and 1,4-disubstituted-1,2,3-triazoles
作者:Hélio A. Stefani、Adriano S. Vieira、Mônica F.Z.J. Amaral、Leora Cooper
DOI:10.1016/j.tetlet.2011.04.072
日期:2011.8
5-alkynyl-1,3-dioxin-4-ones using Suzuki–Miyaura cross-coupling reaction of potassium alkynyltrifluoroborate salts with 2,2,6-trimethyl-5-iodo-1,3-dioxin-4-one. The resulting 5-ethynyltrimethylsilyl-1,3-dioxin-4-ones obtained through the Sonogashira reaction were further reacted in a Cu(I)-catalyzedHuisgenazide–alkyne1,3-dipolarcycloaddition to form functionalized 1,4-disubstituted-1,2,3-triazoles in
An expeditious synthesis of α-aryl- and α-alkynylcyclohexenones is described and illustrated by palladium-catalyzed cross-coupling reaction of cyclic α-iodoenones with potassium aryl-trifluoroborate salts. This procedure offers easy access to α-arylated and alkynylated cyclohexenones functionalized with electrondonor and -acceptor substituents in good yields.