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A convenient and atom-economical protocol for the construction of multisubstituted 2-aminoquinoline N-oxides using readily available starting materials anthranil and arylacetonitrile has been reported. The KHMDS mediated process tolerates various protecting groups of –OH, halo groups, and heterocycles. The ring-opening/reconstruction reaction with C3-aryl anthranils provided densely-arene-substituted 2-aminoquinoline N-oxides, which are otherwise difficult to synthesize. Overall, the ring-opening/reconstruction reaction involves C–O bond cleavage and C–C and C–N bond formation events. [ABSTRACT FROM AUTHOR]

This document provides information on the synthesis and characterization of various isoxazole compounds. The compounds were synthesized using specific reactions and their yields, physical properties, and spectroscopic data are reported. The information presented can be useful for researchers studying isoxazole compounds and their properties. The authors acknowledge the support of DST and SCXRD LAB, SAIF, IIT Madras for single-crystal X-ray analysis. Supporting information for the article is available online. [Extracted from the article]

Pd(II)-catalyzed C–H olefination of aryl 2-pyridyl sulfoxides with unactivated and activated olefins has been demonstrated. We employed environmentally benign and inexpensive molecular oxygen as the sole oxidant. The versatile nature of the 2-pyridyl sulfoxide directing group has been proven by its transformation to the sulfone functionality. Deuterium scrambling experiments and intramolecular kinetic isotopic studies were carried out to gain insights into the reaction pathway. [ABSTRACT FROM AUTHOR]

A general and simple strategy is described for preparing functionally diverse arylvinyl ethers through gold-catalyzed intermolecular addition of electronically and sterically substituted phenols with unactivated alkynes. The addition of phenols to unsymmetrical alkynes has provided the corresponding mixture of regioisomers and multiple hydrophenoxylations of polyphenols with diphenylacetylene are shown.

One-pot treatment of dibenzothiophene dioxides with phenylphosphine and KOH in DMSO at ambient temperature provides the corresponding dibenzophosphole oxides after oxidative workup. Substitution of the endocyclic SO2 unit with PPh could proceed via an intermolecular SNAr reaction of the dioxides with potassium phenylphosphide followed by another SNAr reaction in an intramolecular fashion. Various dibenzophospholes have been synthesized from readily available dibenzothiophene dioxides and were investigated from a photophysical viewpoint. [ABSTRACT FROM AUTHOR]

Treatment of dibenzothiophene dioxides with cyclic diarylmethanes in the presence of KN(SiMe3)2 results in the formation of fluorene-based spirocyclic tetraarylmethanes in a single operation. The transformation would proceed via an intermolecular SNAr reaction of the dioxides with cyclic diarylmethylpotassium followed by intramolecular SNAr cyclization. This straightforward strategy provides a wide range of spirocyclic diarylfluorenes including unusual ones that are otherwise difficult to synthesize. [ABSTRACT FROM AUTHOR]

In this review, we deal with the syntheses of large discrete atomic layers at the molecular level. Spectroscopic measurements as well as X-ray crystallographic analyses lead to unambiguous characterizations of these layers. The molecular atomic layers can be considered to be parts of graphenes and related atomic layers, thereby helping to understand such indefinitely huge atomic layers or serving as seeds for the controlled synthesis of nanocarbons. [ABSTRACT FROM AUTHOR]

Dibenzothiophene dioxides, which are readily prepared through oxidation of the parent dibenzothiophenes, undergo nucleophilic aromatic substitution with anilines intermolecularly and then intramolecularly to yield the corresponding carbazoles in a single operation. The 'aromatic metamorphosis' of dibenzothiophenes into carbazoles does not require any heavy metals. This strategy is also applicable to the synthesis of indoles. Since electron-deficient thiaarene dioxides exhibit interesting reactivity, which is not observed for that the corresponding electron-rich azaarenes, a combination of a thiaarene-dioxide-specific reaction with the SNAr-based aromatic metamorphosis allows transition-metal-free construction of difficult-to-prepare carbazoles. [ABSTRACT FROM AUTHOR]

Dibenzothiophene dioxides undergo nucleophilic aromatic substitution with anilines to form carbazoles in a single operation. [ABSTRACT FROM AUTHOR]

Base-induced redox-isomerization of easily accessible propargyl alcohols followed by conjugate addition of NH heteroarenes gives a series of β-heteroarylated ketones in one step. [ABSTRACT FROM AUTHOR]

Meyer-Schuster rearrangement of 3°-propargyl alcohol to the corresponding α,β-unsaturated carbonyl compounds under SOCl 2 catalysis has been reported. Terminal and internal propargyl alcohols efficiently participated in the reaction. Furthermore, we have demonstrated the synthetic utility of conjugated carbonyl compounds to access densely arene-substituted pyrazolines bearing quaternary centers by reacting with arylhydrazine hydrochloride. Isotopic labeling studies were carried out to gain insights into the reaction mechanism.

A straightforward KHMDS mediated synthetic route to 9-arylfluorenes from readily available starting materials has been developed. This reaction involves SNAr reactions of dioxide with arylacetonitriles, followed by decyanation reaction. The proposed transformation can also be used to furnish a densely arylated indene.

Dibenzothiophene dioxides, which are readily prepared through oxidation of the parent dibenzothiophenes, undergo nucleophilic aromatic substitution with anilines intermolecularly and then intramolecularly to yield the corresponding carbazoles in a single operation. The "aromatic metamorphosis" of dibenzothiophenes into carbazoles does not require any heavy metals. This strategy is also applicable to the synthesis of indoles. Since electron-deficient thiaarene dioxides exhibit interesting reactivity, which is not observed for that the corresponding electron-rich azaarenes, a combination of a thiaarene-dioxide-specific reaction with the SN Ar-based aromatic metamorphosis allows transition-metal-free construction of difficult-to-prepare carbazoles., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)