Structure of 2(5)-alkyl-4-hydroxy-3,4-diphenylcyclopent-2-en-1-ones, cyclocondensation products of benzil with aliphatic ketones

Abstract

The reaction of benzil with methyl alkyl ketones gave three isomeric cyclopentenone derivatives, 2-substituted and cis-and trans-5-substituted 4-hydroxy-3,4-diphenylcyclopent-2-en-1-ones. cis-and trans-2,5-Disubstituted 4-hydroxy-3,4-diphenylcyclopent-2-en-1-ones were formed in analogous reaction of benzil with dialkyl ketones. The structure of the products was confirmed by 1 H NMR spectroscopy and molecularmechanics calculations.

Synthesis of New Pyrazoles via Cycloaddition Reactions of Nitrilimines with 2‐Cyclopentenone Derivatives

“…In the unit cell, the two enantiomers 4 S and 4 R are present (Figure ). Also, the cyclopentenone 8 was obtained from the reaction of benzil with methyl ethylketone .…”

“…A mixture of 2 (5 mmole) , 1 (5 mmole) and triethylamine (1.5 mL) in dry benzene (30 mL) was heated under reflux for 10–35 h. Triethylamine chlorohydrate was removed by filtration, the solvent was evaporated in vacuum, and the residue was chromatographed on silica gel to give compounds 3 , 4 , 5 , 6 , 7 , and 8 .…”

“…Therefore, the synthesis of this type of compounds has attracted considerable attention. In the present work, the cycloaddition reaction of 2‐cyclopentenone derivatives 2 with nitrilimines 1 has been examined.…”

Dependence of Electrical Properties on Frequency and Temperature for Novel Cyclopentenone Derivatives

“…3, 4-Diphenyl-4-hydroxy-2-cyclopentenone (sample 1) was synthesized as previously described in the literature [14] . While the synthesis of 1,3,6,6a-tetraphenyl-1,6a-dihydrocyclopenta[c]pyrazol-4(3aH) one (sample 2) and 1-(3-Chlorophenyl)-3,6,6a-triphenyl-1,6a-dihydrocyclopenta[c]pyrazol-4(3aH)-one (sample 3) were synthesized using literature [15] .…”