Acid-mediated decarboxylative C–H coupling between arenes and O-allyl carbamates

Abstract

Treatment of O-allyl N-tosyl carbamates with aromatic compounds in the presence of Cu(OTf)2 or TMSOTf as promoters, affords N-substituted 1-arylpropan-2-amines, 1,2-diarylpropanes, 1,1-diarylpropanes, or indanes, depending on the nature of the...

Copper(II)-Catalyzed Three-Component Arylation/Hydroamination Cascade from Allyl Alcohol: Access to 1-Aryl-2-sulfonylamino-propanes

“…Our investigation began with the evaluation of the reaction conditions previously adopted with the O -allyl carbamates . Accordingly, reacting allyl alcohol with 2.0 equiv of tosylamide in the presence of 4.0 equiv.…”

“…synthetic equivalents. 5 Indeed, in that case, strongly activated arenes such as 1,4-dimethoxybenzene and 1,3,5-trimethoxybenzene selectively led to 1,2-diarylation products rather than the arylation/hydroamination products 6−7, whereas the reaction carried on with anisole gave a mixture of the two possible regioisomers 12a/12b.…”

“…Conversely, treatment of α,αand γ,γ-dimethyl-substituted allyl alcohols afforded only diarylated derivatives with indane structures. 5,17 The above outcome can be interpreted as follows. Protonation of crotyl alcohol or 3-buten-2-ol generates the common allylic carbenium ion VI that is intercepted by the arene to give a crotylated arene.…”

“…5, 145.8, 134.1, 133.9, 132.2, 130.3, 127.5, 123.6, 51.4, 36.9, 23.3, 20.5, 16. (d, 3H, J = 6.5 Hz); 13 C{ 1 H} NMR (CDCl 3 , 101 MHz) δ 137. 5, 137.1, 134.1, 133.8, 132.6, 132.5, 132.4, 130.4, 129.7, 125.8, 50.0, 37.1, 22.1, 20.6, 19.8, 16. [1][2]3,5,. 1,2,4,5-Tetramethylbenzene (671.1 mg), 2-nitrobenzenesulfonamide (404.4 mg); FCC−AcOEt/hexane (4:1), R f : 0.37.…”

Pd-Catalyzed Regioselective Intramolecular Allylic C–H Amination of 1,1-Disubstituted Alkenyl Amines

“…For instance, Pd-catalyzed aza-Wacker-type oxidative amination and TM- or Lewis acid-catalyzed hydroamination furnish a new C–N bond between a nitrogen atom and an alkenyl sp 2 carbon atom in alkenyl amines (path a, Scheme a), and vinyl or allenyl ethers and amines with a tethered N -nucleophile are required as substrates when synthesizing oxazolidines and imidazolidines through these processes . Conversely, although allyl ethers and amines can be more readily prepared via common allylation, they have rarely been employed as the substrates for these processes (Scheme b). − When considering well-established Tsuji–Trost type allylic substitution involving C–O or C–N bond cleavage (path b), acyclic products can be formed with the loss of an X atom while deallylation as a potential side reaction can be problematic.…”