A new strategy for the aza-Michael reaction of amides and ureas with α,β-unsaturated enones, which uses p-TsOH·H2O as an efficient and inexpensive catalyst under high-pressure conditions, has been developed.
Palladium-Catalyzed Hydroamidation Reaction of Enones
作者:Kiyosei Takasu、Masataka Ihara、Naoko Nishida
DOI:10.1055/s-2004-830852
日期:——
A catalytic amount of Pd(PhCN)2Cl2 promotes conjugate addition reaction of amides with enones to afford β-amidoketones (aza-Michael reaction, hydroamidation reaction) under solvent-free conditions. The produced β-amidoketones could be transformed into multi-substituted piperidinones.
作者:Jinhong Chen、Hao Wang、Craig S. Day、Ruben Martin
DOI:10.1002/anie.202212983
日期:2022.12.12
A Ni-catalyzed site-selective intermolecularC(sp3)−H amidation has been developed. This protocol is characterized by its mild conditions, broad substrate scope, and excellent chemo- and site-selectivity, thus unlocking a complementary technique to conventional C(sp3)−N bond-forming reactions for accessing amine architectures from simple building blocks.
Catalytic Conjugate Additions of Nitrogen-, Phosphorus-, and Carbon-Containing Nucleophiles by Amphoteric Vanadyl Triflate
作者:Yow-Dzer Lin、Jun-Qi Kao、Chien-Tien Chen
DOI:10.1021/ol702302y
日期:2007.12.1
A series of carbamates, amides, N-tosyl amides, (hetero)arenes, and hydrogen phosphines/phosphites has been examined as nucleophiles for (hetero)Michael-type additions to enones and enamides catalyzed by amphoteric vanadyl triflate under mild and neutral conditions. The newly developed C-N, C-P, and C-C bond-formation protocols were carried out smoothly in good to high yields without intervention of any 1,2-additions.
Thionation ofω-Acylamino Ketones withLawesson's Reagent: Convenient Synthesis of 1,3-Thiazoles and 4H-1,3-Thiazines
The reaction of omega -acylamino ketones with Lawesson's reagent (=2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide; LR) is described. Treatment of 2-acylamino ketones 1 (n = 0) with LR gave 1,3-thiazole derivatives 3 in good yields (Scheme I and Table 1). The 4H-1,3-thiazines 4 were obtained as main products by treatment of 3-acylamino ketones 2 (n = 1) with an equimolar amount of LR, while mainly the corresponding 3-(thioacyl)amino ketones 5 were isolated when 0.5 equiv. of LR was used. The 3-acylamino esters 7 also reacted with LR to give the corresponding 3-(thioacyl)amino esters 8 (Scheme 3 and Table 2).