Juan Fan

A Convenient Synthesis of N-Aryl Benzamides by Rhodium-Catalyzed ortho-Amidation and Decarboxylation of Benzoic Acids

The rhodium-catalyzed amidation of substituted benzoic acids with isocyanates by directed CH functionalization followed by decarboxylation to afford the corresponding N-aryl benzamides is demonstrated, in which the carboxylate serves as a unique, removable directing group. Notably, less common meta-substituted N-aryl benzamides are generated readily from more accessible para- or ortho-substituted groups by employing this strategy.

Ru(II)-catalyzed ortho -amidation and decarboxylation of aromatic acids: a versatile route to meta -substituted N -aryl benzamides

Carboxylate as a promising and valuable directing group has attracted a great deal of attention. However, employing it as a traceless direction group has rarely been reported. We developed the ruthenium-catalyzed amidation of substituted benzoic acids with isocyanates via directed C-H functionalization followed by decarboxylation to afford the corresponding meta-substituted N-aryl benzamides, in which the carboxylate serves as a unique, removable directing group. Notably, this protocol can provide an efficient alternative to access meta-substituted N-aryl benzamides, which are much more difficult to prepare than ortho-substituted analogues.

Catalyst‐Free Three‐Component Tandem CDC Cyclization: Convenient Access to Isoindolinones from Aromatic Acid, Amides, and DMSO by a Pummerer‐Type Rearrangement

A catalyst-free multicomponent CDC reaction is rarely reported, especially for the intermolecular tandem CDC cyclization, which represents an important strategy for constructing cyclic compounds. Herein, a three-component tandem CDC cyclization by a Pummerer-type rearrangement to afford biologically relevant isoindolinones from aromatic acids, amides, and DMSO, is described. This intermolecular tandem reaction undergoes a C(sp(2) )-H/C(sp(3) )-H cross-dehydrogenative coupling, C-N bond formation, and intramolecular amidation. A notable feature of this novel protocol is avoiding a catalyst and additive (apart from oxidant).

Ruthenium (II)-catalyzed synthesis of phthalides via the cascade addition and cyclization of aromatic acids with aldehydes

The ruthenium-catalyzed intermolecular cascade cyclization of aromatic acids with aromatic aldehydes, which involves the direct insertion of C–H bond into a polar C=O bond and the successive intramolecular nucleophilic substitution, was developed for the synthesis of 3-substituted phthalides in good to excellent yields. This one-pot procedure characterizes in a short reaction time, the cheaper Ru(II) as a catalyst, readily available acids and aldehydes as starting materials, and water as the only theoretical by-product. These merits make the protocol an efficient and cost-effective route for the synthesis of 3-substituted phthalides.

Iron-Catalyzed Alkylation of Nitriles with Alcohols

A general, efficient iron-catalyzed α-alkylation of nitriles with primary alcohols through a hydrogen-borrowing pathway has been developed, allowing a wide variety of alkylated nitriles to be readily accessible. Detailed mechanistic studies suggest that the reaction proceeds via an olefin intermediate with the turnover rate limited by the hydrogenation of the olefin with an iron hydride. Apart from participating in the alkylation, the nitrile is found to play an important role in promoting the formation of and stabilizing the active catalytic species.

Immobilized bis-layered ionic liquids/peroxotungstates as an efficient catalyst for selective oxidation of alcohols in neat water

An immobilized ionic liquids/peroxotungstates/SiO2 catalyst was prepared and characterized. The catalyst was proved to be very efficient for the selective oxidation of primary and secondary alcohols to their corresponding carbonyls with benign H2O2 as an oxidant in neat water. A 1.0 mol% (based on tungstate) dose of the catalyst was found to be sufficient for the oxidation. The catalyst is easily recovered after reaction via simple filtration, and was reused at least six times without a noticeable loss of the activity. A notable feature of this novel protocol is avoiding any organic co-solvent.