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Highly enantioselective halocyclization reactions of indole derivatives, including tryptophols and tryptamines, have been accomplished by means of anionic chiral Co(III) complexes and 1,3-dihalohydantoins (as little as 0.50 equiv). 3-Halo-fused indolines were obtained in excellent yields (up to 98%) and enantioselectivities (up to 98% ee), employing the chiral anion phase-transfer-catalysis strategy.

The chiral Co(III)-complex-templated Bronsted acids were used as efficient bifunctional phase-transfer catalysts for the asymmetric intermolecular iodoacetalization of enol ethers, such as 3,4-dihydro-2H-pyran, 2,3-dihydrofuran, ethyl vinyl ether with alcohols and NIS, furnishing the 3-iodoacetals in high yield with up to 83:17 er.

We report the first allylic isomerization of alcohols catalyzed by nBu4NOTf generated in situ from tetrabutylammonium triflate and potassium tert-butoxide. Substituted ketones could be prepared under mild conditions in good to excellent yields. The relationship between catalysts and their reactivity has been investigated by systematic kinetic studies. The radical nature of this isomerization reaction has also been confirmed.

An aldehyde-selective aerobic Wacker-Tsuji oxidation is developed. Using tert-butyl nitrite as a simple organic redox cocatalyst instead of copper or silver salts, a variety of aldehydes were achieved as major products in up to 30/1 regioselectivity as well as good to high yields at room temperature.

A pharmaceutical-oriented, transition-metal-free, cyanide-free one-step direct transformation of methylarenes to aryl nitriles is described. For the dimethylarenes, the selectivity can be well-controlled to form mononitriles or dinitriles. Enantioenriched nitriles can also be synthesized by this method. As a pharmaceutically practical method, the antidepressant drug citalopram was synthesized from cheap and commercially abundant m-xylene on a gram scale in high yield, avoiding transition-metal residues and toxic cyanides.

A transition-metal-free deacylative C(sp(3))-C(sp(2)) bond cleavage for the synthetically practical oxidative amination of ketones and aldehydes to nitriles is first described, using cheap and commercially abundant NaNO2 as the oxidant and the nitrogen source. Various nitriles bearing aryl, heteroaryl, alkyl, and alkenyl groups could be smoothly obtained from ketones and aldehydes in high yields, avoiding highly toxic cyanides or transition metals.

A base-catalyzed/promoted transition-metal-free direct alkylation of amines with alcohols has been developed, giving the desired amines in generally high yields from either aromatic or aliphatic alcohols. On the basis of the (1)H NMR and in situ IR (React-IR) monitoring experiments, isotope-labeling experiments, as well as control experiments, a novel "hemiaminal" model is proposed to understand the mechanism, which explains the formation of the "extra" aldehyde in the reaction.

Sodium borohydride reduction in aprotic solvents has always been an unsolved problem. In this work a ion-pair-catalyzed sodium borohydride reduction in aprotic solvents was kinetically and mechanistically studied. Finally sodium borohydride reduction could be carried out in common aprotic solvents efficiently under mild conditions. A large quantity of water or methanol as the solvent or co-solvent has been avoided. The generation of stoichiometric or excess organic ammonium waste has also been avoided. The normal acidic work-up is not necessary and the catalyst was recycled.

An unprecedented base-promoted direct olefination of aryl alcohols with sulfones via a Julia-type reaction has been described. No extra reductants are needed for Julia reaction since alcohols work as double sources of aldehydes and the hydride. Generally high yields were given for both terminal and highly (E)-selective internal olefins.

An aldehyde-selective aerobic Wacker–Tsuji oxidation is developed. Using tert-butyl nitrite as a simple organic redox cocatalyst instead of copper or silver salts, a variety of aldehydes were achieved as major products in up to 30/1 regioselectivity as well as good to high yields at room temperature.

Triflic acid-catalyzed direct oxidative lactonization of alkenoic acids mediated solely by NaIO4 without halogen salts is described. Sodium periodate works not only as an oxidant, but also as an active reagent and directly mediates the lactonization. A new cheap, green, and practical oxidative lactonization approach has been developed using NaIO4 as the sole reagent.

Triflic acid-catalyzed direct oxidative lactonization of alkenoic acids mediated solely by NaIO4 without halogen salts is described. Sodium periodate works not only as an oxidant, but also as an active reagent and directly mediates the lactonization. A new cheap, green, and practical oxidative lactonization approach has been developed using NaIO4 as the sole reagent.

An efficient and practical transformation of various benzylic or aliphatic methyl ketones to nitriles is described.

Phenanthroline and tert-butoxide have been established as powerful radical initiators in reactions such as the SRN1-type coupling reactions due to the cooperation of large heteroarenes and a special feature of tert-butoxide. The first phenanthroline-tert-butoxide-catalyzed transition-metal-free allylic isomerization is described. The resulting ketones are key intermediates for indenes. The control experiments rule out the base-promoted allylic anion pathway. The radical pathway is supported by experimental evidence that includes kinetic study, kinetic isotope effect, isotope-labeling experiments, trapping experiments, and EPR experiments.

Both sulfonamides and arylamines are alkylated with alcohols and a novel hemiaminal model is proposed as the possible intermediate.

Phenanthroline and tert-butoxide have been established as powerful radical initiators in reactions such as the SRN1-type coupling reactions due to the cooperation of large heteroarenes and a special feature of tert-butoxide. The first phenanthroline-tert-butoxide-catalyzed transition-metal-free allylic isomerization is described. The resulting ketones are key intermediates for indenes. The control experiments rule out the base-promoted allylic anion pathway. The radical pathway is supported by experimental evidence that includes kinetic study, kinetic isotope effect, isotope-labeling experiments, trapping experiments, and EPR experiments.

A highly efficient ruthenium-catalyzed stereospecific N-demethylative rearrangement of isoxazolidines to synthetically useful N-H-1,3-oxazinanes is described. 1,3-Oxazinanes are useful building blocks, which can be further converted to N-H-1,3-aminoalcohols in one step. This new method was used in a three-step gram-scale total synthesis of HPA-12 in an overall 24% yield.

A base-promoted direct olefination of aryl alcohols with sulfones via a Julia-type reaction is established.

An asymmetric N-demethylative rearrangement of 1,2-isoxazolidines catalyzed by ruthenium is described. Enantioenriched syn-1,3-aminoalcohols as well as cis-1,3-oxazinanes, which are useful building blocks, can be efficiently prepared stereospecifically by this reaction in good yields, via the isoxazolidine intermediates in situ generated from a nitrone bearing a chiral auxiliary and styrenes. This asymmetric reaction was also applied in the asymmetric total syntheses of both (−)-(1R,3S)-HPA-12 and (+)-(1S,3R)-HPA-12.

A straightforward synthesis of syn-1,3-aminoalcohols as well as their N-methyl derivatives is achieved by Ru-catalyzed rearrangement of isoxazolidines and subsequent aminolytic or reductive ring opening.

An asymmetric N-demethylative rearrangement of 1,2-isoxazolidines catalyzed by ruthenium is described. Enantioenriched syn-1,3-aminoalcohols as well as cis-1,3-oxazinanes, which are useful building blocks, can be efficiently prepared stereospecifically by this reaction in good yields, via the isoxazolidine intermediates in situ generated from a nitrone bearing a chiral auxiliary and styrenes. This asymmetric reaction was also applied in the asymmetric total syntheses of both (−)-(1R,3S)-HPA-12 and (+)-(1S,3R)-HPA-12.

A strategy of ruthenium-catalyzed self-hydride transferring cleavage of N–O bonds was designed and utilized in a cascade 1,3-dipolar cyclization of alkenes and N-methyl nitrones followed by an N-demethylative rearrangement, furnishing synthetically useful N–H 1,3-oxazinanes.

A strategy of ruthenium-catalyzed self-hydride transferring cleavage of N–O bonds was designed and utilized in a cascade 1,3-dipolar cyclization of alkenes and N-methyl nitrones followed by an N-demethylative rearrangement, furnishing synthetically useful N–H 1,3-oxazinanes.