Fe(III)/ l -Valine-Catalyzed One-Pot Synthesis of N -Sulfinyl- and N -Sulfonylimines via Oxidative Cascade Reaction of Alcohols with Sulfinamides or Sulfonamides
An efficient Fe(III), l -valine, and 4-OH-TEMPO catalytic system was found for the oxidation of alcohols followed by condensation with sulfinamide or sulfonamide in one pot for the synthesis of N -sulfinyl- and N- sulfonylimines compounds under mild conditions. This transformation accommodates a variety of substrates, shows high functional-group tolerance, and affords the corresponding products in good to excellent yields.
Direct synthesis of N-sulfinyl- and N-sulfonylimines via copper/l-proline-catalyzed aerobic oxidative cascade reaction of alcohols with sulfinamides or sulfonamides
An efficient one-pot synthetic method of N-sulfinyl- and N-sulfonylimines by the condensation of alcohols with sulfinamides or sulfonamides under mild and green conditions has been developed using a combination of CuI, l-proline and TEMPO. This system shows excellent functional group compatibility for a wide range of substrates and affords the corresponding products in good to excellent yields.
Catalytic asymmetric synthesis of β-sultams as precursors for taurine derivatives
β-Sultams, biologically interesting sulfonyl analogues of β-lactams, have been prepared by an organocata-lytic asymmetric formal [2+ 2]-cycloaddition approach of non-nucleophilic imines with alkyl sulfonyl chlorides. In the case of very electron poor N-to
Zajac, Marian,Peters, Rene
supporting information; experimental part
p. 8204 - 8222
(2011/02/27)
Lewis base assisted Bronsted base catalysis: Bidentate phosphine oxides as activators and modulators of bronsted basic lanthanum-aryloxides
(Chemical Equation Presented) Dynamic Duo: A Lewis basic bidentate phosphine oxide was effective for activating and modulating the properties of Bronsted basic lanthanum aryl oxides. The Lewis base 1/lanthanum aryl oxide system was suitable for anti-selective Mannich-type reactions of trichloromethyl ketones (see scheme), affording unique building blocks for azetidine-2-carboxylic acids as well as β-amino acids.
Enantioselective C-C bond formation to sulfonylimines through use of the 2-pyridinesulfonyl group as a novel stereocontroller
Enantioselective C-C bond formation to 2-pyridinesulfonylimines afforded products with good enantioselectivity. Dynamic induction of chirality on the sulfur by coordination of a chiral Lewis acid to the pyridine nitrogen and one of the prochiral sulfonyl oxygens induces enantioselectivity. Since the 2-pyridine-sulfonyl group can easily be removed after the reaction, it acts not only as an activating group but also as an efficient Stereocontroller.