Synthesis of N-Pyrrolyl(furanyl)-Substituted Piperazines, 1,4-Dizepanes, and 1,4-Diazocanes

Abstract

The synthetic potential of 5-bromo-1,1,1-trifluoro-4-methoxypent-3-en-2-one toward the catalyst-free synthesis of N-pyrrolyl(furanyl)-piperazines, 1,4-diazepanes, and 1,4-diazocanes through a telescoped protocol is reported. This threecomponent one-pot method provided 23 examples with high chemo-and regioselectivity at yields up to 96%.

Brominated β-Alkoxyvinyl Trihalomethyl Ketones as Promising Synthons in Heterocyclic Synthesis

“…However, the amine added to intermediate 38 allowed the synthesis of a series of stable Npyrrolyl-1,4-diazacycles in 44-71% yields, by refluxing in CHCl 3 for 1 h. When the solvent was replaced by ethanol and the Na 2 CO 3 was added instead of the amine, N-furyl-1,3-diazacycles were obtained in 89-96% yields. 34…”

The Wonderful World of β‐Enamino Diketones Chemistry

“…Speaking in terms of reactivity toward a nitrogen nucleophile (e.g., hydrazine or amines), according to reports in the literature for parent structures, the 1,4‐conjugated addition is expected to occur first, followed by nucleophilic addition at the carbonyl carbon. [ 27–31 ] This may become an issue when dealing with the 1,3‐diketone, given that there are two carbonyls that may experience the addition, which could furnish a mixture of two products (Scheme 3).…”

Divergent and Regioselective Synthesis of (Trifluoromethyl/carboxyethyl)benzo[4,5]imidazo[1,2‐a]pyrimidines from β‐Enamino Diketones

“…[ 19–21 ] Even though the chemistry of carboxyethyl β‐enamino diketones 1 has been explored, [ 22–29 ] trifluoromethyl 2 ones have been far less used in heterocyclic synthesis. [ 21,30–34 ] Thus, this work aims to study the cyclocondensation reaction between β‐enamino diketones ( CCC building blocks) and 2‐aminobenzimidazole ( NCN ‐dinucleophile), observing the regioselectivity of the obtained products.…”