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A tunable copper-catalyzed azide–alkyne cycloaddition (CuAAC)-initiated multicomponent reaction strategy for the construction of 3-functionalized indolin-2-ones is reported. Upon controlling the ring opening of four-membered O-heterocyclic intermediates, this unique method enables the divergent derivatization of N-protected isatins to give three-component (3-CR) and four-component (4-CR) adducts, respectively.

An efficient, mild, and convenient method for the preparation of 2,3-dihydrothieno(2,3-b)quinolines and thieno(2,3-b)-quinolines via an unexpected domino aza-Morita–Baylis–Hillman/alkylation/aldol reaction has been developed. The plausible mechanisms for the unexpected reaction are also given.

Using Takemoto′s organocatalyst, the reaction between (E)-β-nitrostyrenes (II) and N-aryltetralon-2-carbothioamides (I) or (IV) gives the spiro compounds (III) and (V) with excellent chemo-, regio-, diastereo-, and enantioselectivities.

On the basis of the reaction of (E)-4-methyl-1-phenylpent-2-en-1-one with chalcone and derivatives in ionic liquids [BMIM]PF6, highly regio-and diastereo-selective syntheses of 1,5-dicarbonyls have been achieved.

The asymmetric domino reaction of various nitro-chromene derivatives to 3-isothiocyanato oxindole (II) proceeds with good enantioselectivities, employing a readily available bifunctional thiourea as the organocatalyst.

The catalyst-free sulfa-Michael/aldol cascade reaction of chalcones (I) and (V) with diol (II) proceeds under mild conditions to form spirotetrahydrothiophene derivatives.

A one-step method for the construction of cross-conjugated enediyne-imides is presented as well as their Pd-catalyzed reaction with allylic bromides to yield 3,5-diallylfuropyridines (VI) and (VIII).

A chiral multiple catalysis with two chiral units has been proved effective in the domino Friedel–Crafts alkylation of β-naphthols with α-bromonitroalkenes. This novel and efficient domino reaction affords chiral 1,2-dihydronaphtho[2,1-b]furans in good to high yields and enantioselectivities (up to 93 % yield, 91 % enantiomeric excess).

A new domino alkylation-cyclization-air oxidation of 2-halo-1,3-dicarbonyl compounds such as (II) and (V) with 2-aminophenols (I) is developed.

Benefited by the accessible ynamido–lithium intermediates Ib from a Cu-catalyzed azide–alkyne cycloaddition in the presence of stoichiometric amounts of LiOH, a mild and flexible three-component route to conjugated enyne scaffolds was successfully achieved via a formal E-selective olefination strategy.

With triethylamine as a catalyst, the 1,3-dipolar cycloaddition of azomethine ylides with 3-substituted coumarins proceeded smoothly under mild conditions to afford the desired products benzopyrano[3,4-c]pyrrolidines in good to excellent yields.

A wide range of mono-, bi-, and tricyclic dihydrofurans can be prepared in good yields and high stereoselectivity.

The first highly regio-, chemo-, and enantio-selective direct vinylogous Michael addition of 3-cyano-4-methylcoumarin derivatives to α,β-unsaturated ketones is described, employing readily available 9-amino-9-deoxy-epiquinine as the iminium organocatalyst.

A simple method for the synthesis of diversely functionalized tricyclic tetrazoles from functionalized α,β-unsaturated ketones and malononitrile is described.

Kinetic resolution of nitrochromene derivatives (I) in the presence of benzylidene imine (II) proceeds smoothly in the presence of Takemoto′s bifunctional thiourea catalyst to give a mixture of enantioenriched nitrochromenes ((R)-I) and cycloadduct (III).

Enzymatic syntheses of bioacitive pentapeptide, N-protected Leu-enkephalin and some other oligopeptides in organic solvents were studied. The stereoselectivity of the enzymatic reaction was examined by using racemic substrates. Different enzymes, solvent systems and protecting groups were compared. The importance of the essential water was addressed. The side chain of tyrosine was not protected during all the enzymatic reactions. P-DL-AlaOY (P=Z or Boc, YH or Me) and P-DL-TyrOEt were coupled with GlyNHNHPh by papain and α-chymotrypsin in mixed solvent or organic solvent to obtain the expected optically pure products P-L-AlaGlyNHNHPh and P-L-TyrGlyNHNHPh respectively in good yield. Two sweetener precursors, ZAspXaaOR (XaaOR=PheOMe or AlaOcHex) were synthesized by thermolysin in tert -amyl alcohol and some reaction conditions were optimized to get the best yield. Full enzymatic synthesis of N-protected Leu-enkephalin ZTyrGlyGlyPheLeuOH was investigated using α-chymotrypsin and thermolysin as catalysts in dichloromethane and tert -amyl alcohol.

The asymmetric synthesis of functionalized 2-amino-2-chromene derivatives with high enantioselectivities via one-pot tandem reactions of functionalized α,β-unsaturated ketones with malononitrile catalyzed by 9-amino-9-deoxyepiquinine (1a) in combination with (R)-1,1′-binaphth-2,2′-diyl hydrogen phosphate (1c) is reported for the first time.

The one-pot synthesis of multisubstituted pyrazole derivatives was achieved viacatalyst-free 1,3-dipolar cycloaddition of ethyl diazoacetate and nitroalkenes as the key step and elimination of the leaving group (NO2 or Br) followed by intramolecular proton transfer with satisfactory yields.

Seven novel chiral C2-symmetric substituted bisoxazoline ligands containing 2,5-di(m-substituted)phenyl-1,3,4-oxadiazole have been synthesized from 2,5-di-(m-carboxylphenyl)-1,3,4-oxadiazole and aminoalcohol by NaOH or Et3N cyclization method via halogenated amide intermediate.