Indium (III) mediated Markovnikov addition of malonates and β-ketoesters to terminal alkynes and the formation of Knoevenagel condensation products

Indium-catalyzed, novel route to β,β-disubstituted indanones via tandem Nakamura addition–hydroarylation–decarboxylation sequence

“…Increase in yield (62%) was observed when we carried out the model reaction in refluxing toluene for 16 h. As the reaction is believed to progress in a tandem manner, we predict that the isolation of an intermediate (which may be the product of any one chemical transformation) would provide a clear note about the reaction pathway. In agreement with Zhang's report, 10 the formation of isomerised Nakamura product 3a 0 was observed within 5 h in 80% yield (Scheme 2, step a) as E : Z isomeric mixture. In case of unsubstituted b-keto esters, after the formation of Nakamura product, they would isomerize to a Knoevenagel-type product.…”

Design and Synthesis of Orally Bioavailable 4-Methyl Heteroaryldihydropyrimidine Based Hepatitis B Virus (HBV) Capsid Inhibitors

“…First, tetrasubstituted olefin 29 was obtained by one-step indium­(III)-catalyzed condensation of β-ketoester 8 and alkyne 28 in 40% yield (Scheme ). Second, the condensation of 29 and thiazole-2-carboxamidine was carried out as described before and the product 7a was converted to bromide intermediate 30 for chemical diversification. Finally, in the case of N-linked analogues, 30 was treated with selected amines or (sulfon)­amides ( 32 ) and complementary bases such as K 2 CO 3 and t -BuOK in DMF.…”

Lewis Base-Catalyzed Enantioselective Conjugate Reduction of β,β-Disubstituted α,β-Unsaturated Ketones with Trichlorosilane: E/Z-Isomerization, Regioselectivity, and Synthetic Applications

“…According to General Procedure A, the reaction of ( E )-4-phenylpent-3-en-2-one (80.1 mg) and cyclohexyl methyl ketone (63.1 mg) at rt for 1 h gave dienone 1v as a yellow oil (112.2 mg, 84%, E / Z = 87:13). ( E,E )-Isomer: TLC R f 0.67 (hexane/AcOEt = 7:1, stained purple with anisaldehyde).…”