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As a promising pharmacophore, sulfondiimines have drawn increasing attention in recent years, but their uptake in medicinal chemistry is jeopardized by the scarcity of related transformations. Herein, we report a facile and mild N -alkylation protocol of N H-diphenyl sulfondiimines with alkyl halides to prepare a myriad of N -alkylated diphenyl sulfondiimines. Owing to air atmosphere, room temperature, as well as mild reaction conditions, this protocol has exhibited great potential in organic synthesis and medicinal chemistry by the late-stage functionalization of natural products. [ABSTRACT FROM AUTHOR]

Alkyl halides are readily available starting materials for various synthetic transformations, including Minisci-type C–H functionalizations of hetarenes. The existing methods, however, often require harsh reaction conditions, such as the use of acids, sacrificial electron donors, or radical precursors in excess amounts. Here, we outline recent developments in this field and we highlight our group̓s efforts to achieve fully catalytic photoredox Minisci-type alkylations supported by noncovalent interactions under mild aqueous conditions. [ABSTRACT FROM AUTHOR]

In this work, we disclosed that diphenyl oxalate serves as a CO surrogate to enable a Ni-catalyzed carbonylation of alkyl bromides/tosylates to afford dialkyl ketones. The reaction shows broad substrate scope and good functional group tolerance. [ABSTRACT FROM AUTHOR]

A coupling reaction between cyclic N -acyliminium ions with organozinc reagents is described. The cyclic N -acyliminium ions, generated in situ from N -substituted-5-hydroxy-2-pyrrolidinones by treatment with boron trifluoride–diethyl ether complex or titanium tetrachloride, are trapped by the organozinc reagent, which is formed from an alkyl bromide in the presence of zinc in the same reaction medium. The N -substituted-5-allyl-2-pyrrolidinones generated using this method serve as versatile intermediates for the synthesis of azabicyclic systems with indolizidine and pyrroloazepinolizidine cores. [ABSTRACT FROM AUTHOR]

Although 2-hydroxybenzaldehyde acylhydrazones, such as salicylaldehyde acylhydrazones, are intriguing bioactive molecules, few of their N-alkylated derivatives are known, and only methyl analogues have been reported previously. We achieved selective N-alkylation of 2-hydroxybenzaldehyde acylhydrazones, as their Fe(III) complexes, by using combinations of alkylating agents (for example, an alkyl bromide and a dialkyl sulfate). Fifteen substrates were examined, and 45 new 2-hydroxybenzaldehyde acyl(alkyl)hydrazones were synthesized in moderate to good yields. In all cases, the target products were obtained exclusively, and no O-alkylation byproducts were produced. The method provides an efficient way of preparing 2-hydroxybenzaldehyde acyl(alkyl)hydrazones. [ABSTRACT FROM AUTHOR]

A palladium catalyst in combination with two types of phosphine ligands efficiently catalyzes direct C--H alkylation of heteroarenes with secondary and tertiary alkyl bromides under irradiation conditions. Irradiation of blue light-emitting diodes (blue LEDs) effectively excites phosphine-ligated palladium catalyst to facilitate oxidative addition with alkyl bromides, and also excites the alkylpalladium species to enable the generation of alkyl radicals to react with heteroarenes. [ABSTRACT FROM AUTHOR]

The synthesis of 2-alkylated pyridines by the nickel-catalyzed cross-coupling of two electrophiles, a 2-chloropyridine and an alkyl bromide, is described. Compared with our previously published conditions for aryl halides, this method uses a different, more rigid, bathophenanthroline ligand and is conducted at high concentration in N,N-dimethylformamide as solvent. The method displays promising functional group compatibility and the conditions are orthogonal to those for the Stille coupling. [ABSTRACT FROM AUTHOR]

1N-Alkyl-4-aryl-1,2,3-triazoles have been prepared through a multicomponent one-pot protocol from the corresponding (arylethynyl) trimethylsilanes and alkyl bromides. In situ alkyl azide formation and alkyne deprotection followed by copper(I)-catalyzed click cycloaddition afforded the desired 1,4-disubstituted 1,2,3-triazoles in generally good to excellent yield, with only minor observation of the undesired 1,5-regioisomeric cycloadduct. The protocol eliminates the need to use reactive organic azides and terminal alkynes. [ABSTRACT FROM AUTHOR]