Highly efficient deprotection of phenolic tetrahydropyranyl and methoxymethyl ethers and sequel cyclization to indanones using Sn(IV)Cl4 catalyst

An Unexpected [3 + 2]-Cycloaddition between Spiro-Epoxyoxindoles and γ-Deconjugated Butenolides Catalyzed by Sc(OTf)3

A unique β-position [3 + 2]-cycloaddition between γ-deconjugated butenolides and spiro-epoxyoxindoles catalyzed by Sc(OTf)3 has been disclosed. A variety of unexpected [3 + 2]-cycloaddition adducts of spiro-oxindoles fused with bicyclic γ-lactones and three consecutive stereocenters have been successfully constructed in good yields (up to 88%) with excellent diastereoselectivities (>20:1) in one single operation under mild conditions, which is difficult to achieve by traditional strategies.

Studies on the Origin of the Stabilizing Effects of Fluorinated Alcohols and Weakly Coordinated Fluorine-Containing Anions on Cationic Reaction Intermediates

Many synthetic methods that use fluorinated alcohols as solvents have been reported, and the fluorinated alcohols have been found to be crucial to the success of these methods. In addition, there have been reports indicating that adding a weakly coordinated fluorine-containing anion, such as BF₄^-, PF₆^-, or SbF₆^-, to fluorinated alcohols can improve yields. The boosting effect of fluorinated alcohols is attributed mainly to hydrogen bond activation. A few studies have suggested that the very polar fluorinated alcohols can stabilize cationic reaction intermediates. However, how they do so and why weakly coordinated fluorine-containing anions improve yields have not been studied in depth. Here, we used quaternary ammonium cations, a quaternary phosphonium cation, and a triaryl-substituted carbocation as models for short-lived cationic intermediates and studied the possible interactions of these cations with fluorinated alcohols and BF₄^-, PF₆^-, or SbF₆^-. On the basis of the results, we propose that the C-F dipoles of fluorinated alcohols and the E-F dipoles (where E is B, P, or Sb) of weakly coordinated fluorine-containing anions stabilized these cations by intermolecular charge-dipole interactions. We deduced that in the same fashion the C-F and E-F dipoles can thermodynamically stabilize cationic reaction intermediates.

BiCl3-Facilitated removal of methoxymethyl-ether/ester derivatives and DFT study of –O–C–O– bond cleavage

An experimental and DFT study of the cleavage of the MOM group mediated by an eco-friendly reagent, bismuth trichloride.

Synthesis of 1-indanones with a broad range of biological activity

This comprehensive review describes methods for the preparation of 1-indanones published in original and patent literature from 1926 to 2017. More than 100 synthetic methods utilizing carboxylic acids, esters, diesters, acid chlorides, ketones, alkynes, alcohols etc. as starting materials, have been performed. This review also covers the most important studies on the biological activity of 1-indanones and their derivatives which are potent antiviral, anti-inflammatory, analgesic, antimalarial, antibacterial and anticancer compounds. Moreover, they can be used in the treatment of neurodegenerative diseases and as effective insecticides, fungicides and herbicides.

A rhodium-catalyzed tandem reaction of N-sulfonyl triazoles with indoles: access to indole-substituted indanones

Rhodium(ii)-catalyzed tandem reaction of N-sulfonyl triazoles with indoles delivered structurally diverse indole-substituted indanones bearing vicinal quaternary carbon centers.

SeO2 in water: a mild and efficient promoter for deprotection of acetyl, methoxymethyl and tetrahydropyranyl ethers and sequel oxidation of methyl/methylene carbons of alpha carbonyl carbon

SeO₂ in water is found as mild and efficient promoter for the deprotection of acetyl, tetrahydropyranyl, methoxymethyl ethers and sequel oxidation of methyl/methylene carbons of alpha carbonyl carbon.

Anti-proliferative activities of flavone–estradiol Stille-coupling adducts and of indanone-based compounds obtained by SnCl4/Zn-catalysed McMurry cross-coupling reactions

Flavone–estradiol adducts and indanophen based tamoxifen analogs are synthesized using SnCl₄–Zn reagent via McMurry reaction and evaluated in human cervical (HeLa) and breast cancer cells (MCF-7 and MDA-MB-231) for the anti-proliferative activity.