Chun Wei Kuo

A convenient new procedure for converting primary amides into nitriles

An operationally simple and high-yielding procedure has been developed for the conversion of primary amides to the corresponding nitriles, using ethyl dichlorophosphate/DBU as the mild dehydrating agent.

Synthesis of isocoumarin derivatives via the copper-catalyzed tandem sequential cyclization of 2- halo-N-phenyl benzamides and acyclic 1,3-diketones

A facile and rapid synthesis of isocoumarin derivatives using a copper-catalyzed tandem C-C/C-O coupling strategy from readily available substrates is described. The reactions of a wide range of 2-iodo-N-phenyl benzamides and acyclic diketones as starting materials were investigated.

Synthesis of Isoxazoline N-Oxides via [Hydroxy(tosyloxy)iodo]benzene (HTIB)-Mediated Oxidative N−O Coupling

An HTIB mediated oxidative N-O coupling strategy for the synthesis of some isoxazoline N-oxide derivatives from β-hydroxyketoximes is described, along with a comparative study of the efficiency of N-O coupling in two different solvents. A plausible mechanism for the conversion is proposed.

Synthesis of indolylquinolines, indolylacridines, and indolylcyclopenta[b]quinolines from the Baylis-Hillman adducts: an in situ [1,3]-sigmatropic rearrangement of an indole nucleus to access indolylacridines and indolylcyclopenta[b]quinolines.

A simple and easy route to the synthesis of a variety of structurally diverse indolylquinolines, indolylacridines, and indolylcyclopenta[b]quinoline derivatives via the reductive cyclization of C-alkylated indole derivatives, derived from acyclic as well as cyclic Baylis-Hillman adducts with indoles, is described. An unusual in situ [1,3]-sigmatropic rearrangement of the indole nucleus was observed during the reductive cyclicization of α-regioselective B-H adducts containing indoles to produce indolylacridines and indolylcyclopenta[b]quinoline derivatives.

An efficient method for the N-bromosuccinimide catalyzed synthesis of indolyl-nitroalkanes

An efficient and practical method for the synthesis of indolyl-nitroalkane derivatives catalyzed by N-bromosuccinimide is described. The generality of this method was demonstrated by synthesizing an array of diverse 3-substituted indole derivatives by the reaction of different β-nitrostyrenes with various substituted indoles. Simple reaction conditions accompanied by good yields of indolyl-nitroalkanes are the merits of this methodology.

Alcohol Mediated Synthesis of 4-Oxo-2-aryl-4H-chromene-3-carboxylate Derivatives from 4-Hydroxycoumarins

The unusual alcohol mediated formation of 4-oxo-2-aryl-4H-chromene-3-carboxylate (flavone-3-carboxylate) derivatives from 4-hydroxycoumarins and β-nitroalkenes in an alcoholic medium is described. The transformation occurs via the in situ formation of a Michael adduct, followed by the alkoxide ion mediated rearrangement of the intermediate. The effect of the different alcohol and nonalcohol media on the reaction was investigated.

Iron/acetic acid mediated intermolecular tandem C–C and C–N bond formation: an easy access to acridinone and quinoline derivatives

An efficient iron/acetic acid mediated one pot reductive cyclization protocol was successfully developed for the synthesis of acridinone and quinoline derivatives. This highly efficient process proceeds under mild conditions, tolerates different functional groups, and provides various substituted acridinone and quinoline derivatives in good to excellent yields. In addition, biologically active compounds also accessed from this method.

Syntheses of indolo[1,2-a]quinazolinone derivatives via palladium catalyzed intramolecular C–H amidation

The synthesis of indolo[1,2-a]quinazolinone starting from 2-iodobenzamide and indole derivatives is reported. In this two-step procedure, indole is N-arylated with 2-iodobenzamide derivatives via Ullman coupling, followed by an intramolecular C–H amidation using a palladium catalyst.

Halonium ion mediated synthesis of 2-halomethylene-3-oxoketoxime derivatives from isoxazoline N-oxides.

A protocol for the N-bromosuccinimide (NBS)- and trichloroisocyanuric acid (TCCA)-mediated synthesis of novel 2-halomethylene-3-oxoketoximes via one-pot halogenation/oxidation of isoxazoline N-oxide derivatives is described here. The keto functionality of 3-ketoximes was selectively reduced by lithiumaluminum hydride to synthesize an unprecedented type of Baylis-Hillman oxime, which underwent N-O coupling to produce new isoxazoline N-oxide derivative.

Palladium-Catalyzed Tandem C–H Functionalization/Cyclization Strategy for the Synthesis of 5-Hydroxybenzofuran Derivatives

A palladium-catalyzed benzoquinone C-H functionalization/cyclization strategy with terminal alkynes was employed for the synthesis of some biologically relevant 2,3-disubstituted 5-hydroxybenzofuran derivatives. The benzoquinone acts as a reactant as well as an oxidant. During the process, an additional alkyne functionality can be introduced at the C3 position of the benzofuran. Base, ligand, and external oxidant are not required in this protocol.