RESUMO
A copper-catalyzed stereoselective phosphono-hydrazonation of terminal alkynes with alkyl carbazates and diarylphosphine oxides is described. This methodology provides facile access to a variety of ß-hydrazonophosphine oxides in satisfactory yields. The reaction proceeds under mild conditions and exhibits good functional group tolerance. A mechanism featuring persulfate-mediated oxidative generation of phosphinoyl radicals and copper-assisted hydrazonation is proposed.
RESUMO
An efficient copper-catalyzed radical hydrazono-phosphorylation of alkenes with hydrazine derivatives and diarylphosphine oxides is described. The reaction provides a general and convenient method toward the synthesis of diverse ß-hydrazonophosphine oxides in satisfactory yields. Based on conducted mechanistic experiments, a mechanism involving Ag-catalyzed oxidative generation of phosphinoyl radicals and subsequent addition to alkenes followed by Cu-assisted hydrazonation is proposed. Moreover, the practicability of the reaction is successfully demonstrated by its successful application on a gram scale.
Assuntos
Alcenos , Cobre , Catálise , Oxirredução , ÓxidosRESUMO
A new approach for the preparation of carbamates via the copper-catalyzed cross-coupling reaction of amines with alkoxycarbonyl radicals generated from carbazates is described. This environmentally friendly protocol takes place under mild conditions and is compatible with a wide range of amines, including aromatic/aliphatic and primary/secondary substrates.
Assuntos
Aminas , Cobre , Carbamatos , Catálise , HidrazinasRESUMO
1,2-Bifuctional thiocyanodiphenylphosphinoylation of alkenes is established through the phosphinoyl radical addition followed by Cu-catalyzed thiocyanation. This one-pot reaction is applicable to a range of aromatic, aliphatic, and cyclic alkenes to afford thiocyanodiphenylphosphinoylated compounds in satisfactory yields.
RESUMO
A tert-butyl hydroperoxide (TBHP)-mediated coupling of sulfonylhydrazides with thiols catalyzed by CuBr2 to afford thiosulfonates via a radical process is described.
RESUMO
A copper-catalyzed efficient and practical method has been developed for the synthesis of 1,2-diketones and α-keto esters. TEMPO was used as a radical initiator and scavenger, oxidizing the cleavage of α-methylene of 1,3-diketones and ß-keto esters to form 1,2-diketones and α-keto esters. This method provided a general way for the formation of 1,2-dicarbonyl compounds.
RESUMO
Air oxidative radical hydroxysulfurization of styrenes initiated by 0.5 mol % of tert-butyl hydroperoxide with arylthiols is described, and a new type of difunctionalization of alkenes was achieved.
RESUMO
Air oxidative radical oxysulfurization of alkynes initiated by 0.5 mol % tert-butyl hydroperoxide with arylthiols is described. The reaction proceeded at room temperature in the presence of 5% mol water to afford selective α-thioaldehydes.
RESUMO
A CuI-catalyzed cross-coupling of alkyl- and phosphorus-centered radicals for C(sp3)-P bond formation is introduced. Diacyl peroxides, generated in situ from aliphatic acids and H2O2, serve as a source for alkyl radicals and also an initiator for the generation of phosphorus radicals from H-P(O) compounds.
RESUMO
A copper-catalyzed difunctional cyano-, thiocyano-, and chlorophosphorylation reaction of alkynes with P(O)-H compounds and coupling partners (TBACN, TMSNCS, TMSCl) is described. The reaction introduces versatile groups (-P(O)R2 and -CN, -SCN, or -Cl) to form tri- and tetrasubstituted alkenyl phosphine oxides/phosphonates regio- and stereoselectively.
RESUMO
A new visible light-mediated photocatalytic decarboxylative oxyphosphorylation of cinnamic acids with diarylphosphine oxides is described. This reaction is performed under mild conditions to afford the corresponding ß-ketophosphine oxides.
RESUMO
A new double functionalization reaction of alkenes through AgNO3-mediated phosphinoyl radical addition followed by Cu(II)-catalyzed amination is introduced. This one-pot, three-component reaction is performed under mild conditions to afford α,ß-aminophosphinoylation products.
RESUMO
A double-functionalization reaction of alkenes through Mn(OAc)3-mediated phosphinoyl radical addition followed by CuCN-catalyzed cyanation is introduced. This one-pot reaction is performed under mild conditions to afford vicinal cyanophosphinoylation products.