Me₃SiOTf Promoted Aza‐Michael Addition Reaction of 1°‐Amides with α,β‐Unsaturated Ketones

Abstract

Lewis acid, Me3SiOTf, has been shown to be a promising promoter for aza‐Michael reaction of relatively acidic primary amide with α,β‐unsaturated ketone. A sries of α,β‐unsaturated ketones was transformed to their corresponding β‐amido ketones with moderate yields under this reaction condition.

Michael addition/pericyclization/rearrangement – a multicomponent strategy for the synthesis of substituted resorcinols

“…The characterization of compound 19 has been reported. 19 Synthesis of methyl 2,6-dihydroxy-3-methyl-5-(2,5-dioxo-1phenylpyrrolidin-3-yl)benzoate (8). To a 4 dram vial was added zinc triflate (4 mg, 0.01 mmol), followed by trans-4-methoxy-3buten-2-one (2) (103 mg, 0.930 mmol) and 4.0 mL of dry DCM.…”

“…In order to explore this transformation, ethyl carbamoyl diazoacetate (19) was synthesized (eqn (4)). 18…”

“…Replacing the CH 2 group in 1 with an NH group could potentially lead to formation of poly-substituted pyridines if the pericyclization/rearrangement transformation is possible with this compound. In order to explore this transformation, ethyl carbamoyl diazoacetate (19) was synthesized (eqn (4)). 18…”

“…The enone substrate 2 was fully consumed; however, the desired adduct 20 was obtained only in 35% yield (eqn ( 5)). Using an alternative procedure in which trialkylsilyl triflate was used to promote an aza-Michael addition of a primary amide and α,β-unsaturated ketones, 19 we were able to synthesize diazoester 20 in 66% yield (eqn ( 5)). In contrast to enedione-diazoester 3, ethyl 2-(3-oxobut-1-enylcarbamoyl) diazoacetate (20) is sufficiently stable to undergo silica gel purification.…”

Hydrogen Bonding in a l-Glutamine-Based Polyamidoamino Acid and its pH-Dependent Self-Ordered Coil Conformation

“…In particular, in the 1 H-NMR spectrum, the peak at~4.0 ppm, attributed to the C-H α to the COOH groups of glutamine units, is probably due to the branches originated by the participation of some amidic NH 2 of the glutamine pendants in the aza-Michael polyaddition (see Supplementary Materials Figure S1b). Some examples of the aza-Michael addition of primor sec-amides in the presence of bases are reported [40,41]. In the case of M-l-Gln, the amide NH 2 addition gives rise to branches and to a corresponding number of terminals.…”