International audienceThe aza-Michael addn. of secondary amines to α,β- or β,β-disubstituted α,β-unsatd. esters was efficiently achieved under high pressure (10-16 kbar) in protic solvents in the absence of any catalyst. The expected cumbersome β-aminoesters bearing a tertiary amine directly connected to a quaternary carbon atom could be isolated in fair to good yields. By using α,β,δ,γ-unsatd. esters (alkyl sorbate), the addn. took place regioselectively in a 1,6 manner and afforded the β,γ-unsatd. δ-aminoesters
Direct Access to Cumbersome Aminated Quaternary Centers by Hyperbaric Aza-Michael Additions. -The aza-Michael addition of secondary amines to α,βor β,β-disubstituted α,β-unsaturated esters is efficiently achieved under high pressure (10-16 kbar) in protic solvents without any catalyst. -(RULEV, A. Y.; AZAD, S.; KOTSUKI, H.; MADDALUNO*, J.; Eur. J. Org. Chem. 2010, 33, 6423-6429, http://dx.doi.org/10.1002/ejoc.201000984 ; INSA, CNRS, Univ. Rouen, F-76821 Mont-Saint-Aignan, Fr.; Eng.) -Bartels 15-042
Urea derivatives Q 0640High-Pressure Organic Chemistry. Part 30. A New Practical Method for the Synthesis of Unsymmetrical Ureas via High-Pressure-Promoted Condensation of 2,2,2-Trichloroethyl Carbamates (Troc-Carbamates) with Amines. -Direct condensation of Troc-carbamates with primary and secondary amines provides a new practical method for the synthesis of a variety of unsymmetrical ureas. -(AZAD, S.; KUMAMOTO, K.; UEGAKI, K.; ICHIKAWA, Y.; KOTSUKI*, H.; Tetrahedron Lett. 47 (2006) 4, 587-590; Lab. Nat. Prod. Synth., Fac. Sci., Kochi Univ., Akebono, Kochi 780, Japan; Eng.) -Mais 17-089
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