Guan-Wu Wang

Direct Ortho-Acetoxylation of Anilides via Palladium-Catalyzed sp2 C−H Bond Oxidative Activation

Various anilides have been directly ortho-acetoxylated through a Pd(OAc)2-catalyzed C-H bond activation process. The amide group in anilides was found to functionalize as an elegant directing group to convert aromatic sp(2) C-H bonds into C-O bonds in high regioselectivity with acetic acid as the acetate source and K(2)S(2)O(8) as the oxidant.

Direct Oxidative Amidation of Aldehydes with Anilines under Mechanical Milling Conditions

Oxone is found to be an effective oxidant for the oxidative amidation of aldehydes with anilines to furnish amides in a one-pot process under mechanical milling conditions.

Palladium-Catalyzed Ortho-Alkoxylation of Anilides via C–H Activation

A palladium-catalyzed ortho-alkoxylation of anilides with both primary and secondary alcohols via ligand-directed C-H activation has been explored. This alkoxylation promoted by catalytic methanesulfonic acid proceeds well at room temperature in most cases and affords aryl alkyl ethers in moderate to good yields.

Rapid and efficient synthesis of poly-substituted quinolines assisted by p -toluene sulphonic acid under solvent -free conditions: comparative study of microwave irradiation versus conventional heating

A rapid and efficient method for the preparation of various poly-substituted quinolines has been developed through the Friedländer condensation of 2-aminoarylketone or 2-aminoarylaldehyde with carbonyl compounds in the presence of p-toluene sulphonic acid, which was achieved by both microwave irradiation and conventional heating under solvent-free conditions.

Palladium-Catalyzed Decarboxylative Ortho Acylation of Azobenzenes with α-Oxocarboxylic Acids

A palladium-catalyzed decarboxylative ortho acylation of azobenzenes with α-oxocarboxylic acids via ligand-directed C-H activation has been explored. The reaction proceeded smoothly with potassium persulfate as the oxidant to afford acylated unsymmetrical azobenzenes in moderate to good yields and tolerated chloro, bromo, iodo, and methoxy groups. Para, ortho, and disubstituted as well as unsymmetrical azobenzenes could be used.

Environmentally benign one-pot multi-component approaches to the synthesis of novel unsymmetrical 4-arylacridinediones

The solvent-free and aqueous conditions used give good yields that cannot be achieved in organic solvents. The current process provides a simple and green method to obtain a variety of novel unsymmetrical acridinediones, which may have potential biological activities.

Palladium-Catalyzed Desulfitative Heck-Type Reaction of Aryl Sulfinic Acids with Alkenes

have emerged since its discovery in the early 1970s. Aryl triflates, aryl diazonium salts, diaryl iodonium salts, aroyl chlorides, and aroyl anhydrides as aryl palladium precursors have subsequently been developed. The unreactive aryl chlorides can also be employed in the Heck reaction by using bulky, electron-rich phosphanes and carbenes as the ligands. In contrast, aromatic organic acids have been seldom utilized in the Heck reaction, and until now only aryl carboxylic acids and aryl phosphonic acids have been described as the source of aryl groups in the Heck reaction (Scheme 1, [Eq. (2) and (3)]). The most striking difference in the reaction mechanisms for the conventional Heck reaction and the Heck-type reaction of aromatic organic acids lies in the different pathways leading to the aryl palladium(II) species. The former is generated by the oxidative addition of aryl halides or pseudohalide species to palladium(0), whereas the latter is produced by the initiation of palladium(II) and decarboxylative C C bond cleavage/ C P bond cleavage. Herein, we disclose the Pd-catalyzed Heck-type reaction of another kind of aromatic organic acid, that is, aryl sulfinic acids, with alkenes initiated by a palladium(II) species (Scheme 1, [Eq. (4)]). In our initial study, we investigated the Heck-type reaction of benzenesulfinic acid (1 a) with styrene (2 a) in the presence of a palladium catalyst (10 mol %) to optimize the reaction conditions with various oxidants and solvents. Silver salts were first chosen as the oxidant with dioxane as the solvent, and it was found that Ag2CO3 was more efficient than AgOAc, affording (E)-stilbene in 76 % and 51 % yield, respectively (entry 2 vs. entry 1, Table 1). In comparison, K2S2O8 and O2 were not proper oxidants and dramati-

Synthesis of Fullerooxazoles : Novel Reactions of [60]Fullerene with Nitriles Promoted by Ferric Perchlorate

The ferric perchlorate-mediated reactions of C 60 with various nitriles in o-dichlorobenzene under nitrogen atmosphere afforded the rare fullerooxazoles, which would be difficult to prepare by other methods. A possible reaction mechanism for the formation of the fullerooxazoles was proposed.

Palladium-Catalyzed Heteroannulation of [60]Fullerene with Anilides via C−H Bond Activation

The palladium-catalyzed reaction of [60]fullerene with a variety of readily available anilides, initiated by C-H bond activation and followed by cyclization, afforded [60]fulleroindolines in a highly regioselective manner. A plausible reaction mechanism was proposed.

Radical Reaction of [60]Fullerene with Phosphorus Compounds Mediated by Manganese(III) Acetate

Radical reaction of [60]fullerene with phosphonates or phosphine oxide mediated by manganese(III) acetate dihydrate in chlorobenzene under three different conditions afforded three different types of phosphorylated fullerenes: singly bonded fullerene dimers 2, hydrophosphorylated fullerenes 3, and acetoxylated fullerene derivatives 4. In addition, interconversions among the three types of phosphorylated fullerene derivatives have also been investigated. A possible reaction mechanism was proposed to explain experimental results.