79893-99-5

Upstream product

• 16616-42-5 p-chlorobenzoylphenylacetylene 
• 2450-71-7 Propargylamine 
• 536-74-3 phenylacetylene 
• 122-01-0 4-chloro-benzoyl chloride 

Downstream Products

• 1034842-54-0 C₂₆H₂₂ClNO 
• 1034842-58-4 C₂₄H₁₇ClFNO 
• 1398057-39-0 4-(4-chlorophenyl)-2-phenyl-1H-pyrrole 

Relevant academic research and scientific papers

One-Pot Synthesis of 2-Acetyl-1 H-pyrroles from N-Propargylic β-Enaminones via Intermediacy of 1,4-Oxazepines

A one-pot two-step protocol for the synthesis of 2-acetyl-1H-pyrroles from N-propargylic β-enaminones was described. When treated with zinc chloride in refluxing chloroform, N-propargylic β-enaminones produced in situ 2-methylene-2,3-dihydro-1,4-oxazepines, which, upon further refluxing in methanol with zinc chloride, afforded 2-acetyl-1H-pyrroles. The process was found to be general for a wide variety of N-propargylic β-enaminones and yielded a diverse range of 2-acetyl-1H-pyrroles in good to high yields with large substrate scope and good functional group tolerance. This operationally easy method may provide a rapid access to functionalized 2-acetyl-1H-pyrroles of pharmacological interest.

A new strategy for the synthesis of pyridines from: N -propargylic β-enaminothiones

A new method for the synthesis of 2,4,5-trisubstituted pyridines from N-propargylic β-enaminothiones is reported. β-Enaminothiones were prepared by thionation of the corresponding β-enaminones with Lawesson's reagent. When treated with diisopropylamine in DMF at room temperature, N-propargylic β-enaminothiones yielded 2,4,5-trisubstituted pyridines in moderate to high yields, along with small amounts of 2-methylene-2,3-dihydro-1,4-thiazepines. The reaction was found to be general for a broad range of N-propargylic β-enaminothiones and tolerated the presence of aromatic, heteroaromatic and aliphatic groups with electron-withdrawing and electron-donating substituents. The method could be widened to the internal alkyne-tethered N-propargylic β-enaminothiones. This operationally simple method may provide rapid access to a library of functionalized pyridines of pharmacological interest.

Synthesis of 2-Aminopyridines via a Base-Promoted Cascade Reaction of N-Propargylic β-Enaminones with Formamides

N-Substituted formamides as nucleophiles react with in situ-generated 1,4-oxazepines from N-propargylic β-enaminones followed by spontaneous N-deformylation to deliver densely substituted 2-aminopyridines in good yields (31-88%). The formyl group is found to be a superior traceless activating group of free amines and would ultimately be removed in situ. This reaction proceeds smoothly at room temperature, in the presence of NaOH as sole additive, without protection from the atmosphere and generates H2O and sodium formate as byproducts.

Base-promoted ring-closing carbonyl-allene metathesis for the synthesis of 2,4-disubstituted pyrroles

A base-promoted ring-closing carbonyl-allene metathesis reaction of N-allenyl β-enaminones (generated in situ from N-propargyl β-enaminones) gives 2,4-disubstituted pyrroles with cleavage of the C(sp)-C(sp3) bond. This transition metal-free procedure generates 1 equiv. of acetic acid as the sole byproduct. A preliminary mechanistic study supports a stepwise [2 + 2] cycloaddition/retro [2 + 2] reaction pathway.

N-propargylic β-enaminones: Common intermediates for the synthesis of polysubstituted pyrroles and pyridines

N-Propargylic β-enaminones have been used as common intermediates for the synthesis of polysubstituted pyrroles and pyridines. Best results have been obtained using DMSO as solvent. In the presence of Cs2CO3 N-propargylic β-enaminone