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An unexpected Cu-catalyzed deoxygenative C2-sulfonylation reaction of quinoline N-oxides in the presence of radical initiator K2S2O8 was developed that used sodium sulfinate as a sulfonyl coupling partner. The mechanism studies indicate that the reaction proceeds via Minisci-like radical coupling step to give sulfonylated quinoline with good chemical yields.

Herein is reported an N-iodosuccinimide-initiated spirocyclopropanation reaction of styrenes with 1,3-dicarbonyl compounds in the presence of white LED light. The reaction proceeds via two C–H and two C–I bond cleavage event, along with two C–C bond formation event, and formation of quaternary centers. These reactions could be carried out at room temperature and tolerated a wide range of substrates, resulting in good to excellent chemical yields. This developed radical reaction provides easy and practical access to spiro[2.4]heptane-4,7-dione derivatives.

The first asymmetric catalytic aldol–cyclization reaction of detrifluoroacetylatively in situ generated enolates with methyl 2-formylbenzoate is reported. This reaction tolerates a wide range of substrates, affording fluorinated quaternary stereogenic α,α-dialkyl/cyclo-alkyl-β-ketoesters with good yields, high diastereo- (94% de) and enantioselectivity (96% ee) at room temperature.

The title coumarins are obtained under sunlight via a cascade of radical iodination, spirocyclization, and ring expansion through ester migration affording the kinetically favoured product.

The title reagent (II) (

A novel metal-free tandem oxidative coupling process for the synthesis of hemiaminal ethers has been developed. This protocol could be applied for the C–N bond formation of electron-deficient trizoles, tetrazoles, carbazoles and indazoles with primary alcohols.

An iridium complex with a newly prepared chiral spiro amino-phosphine ligand efficiently catalyzed the hydrogenation of both β-aryl-β-methyl-nitroalkenes and β-alkyl-β-methyl-nitroalkenes to the corresponding saturated nitroalkanes, which represents the first report of a chiral catalyst that exhibits high enantioselectivity for the challenging hydrogenation of β,β-dialkyl-nitroalkenes.

We demonstrate, that the reactions of in situ generated fluoro-enolates with a range of aliphatic aldehydes can be successfully performed using asymmetric catalyst derived from chiral ligand and Cu(OTf) 2 . The enantioselectivity of the formation of two contiguous stereogenic carbons in these additions was excellent, rendering the developed approach as an important methodological advance in asymmetric catalytic reactions of detrifluoroacetylatively generated fluoro-enolates. This process allows preparation of structurally new pharmaceutically interesting class of 1,3-hydroxy ketones containing C-F quaternary stereogenic center adjacent to secondary hydroxy group.

An efficient cascade trifunctioalization reaction of alkynoates with N-iodosuccinimide has been developed which proceeds through iodination, aryl migration, decarboxylation, and second iodination. This reaction represents an example of 1,1-difunctionalization of the acetylene bond and also provides a new strategy for the preparation of 1,1-diiodoalkenes.

A Cu-catalyzed aerobic oxidative reaction between sulfonyl hydrazides and alcohols has been developed. In this reaction, sulfonyl hydrazides act as the sulfinic acid precursors to react with alcohols, resulting in sulfinic esters with up to 72 % yield. This catalytic system tolerates a wide range of sulfonyl hydrazide substrates, and represents a new strategy for the transformation of readily available sulfonyl hydrazides.

A metal-free cascade functionalization of unactivated C(sp3)—H bonds and cyclization reactions of N-substituted allylbenzamides are developed.

A cascade oxidative difunctionalization reaction of alkynoates for the construction of trisubstituted olefins has been developed. The process undergoes alkylation of a C–C triple bond, 1,4-aryl migration, and decarboxylation, which demonstrates a multistep radical cascade reaction for the difunctionalization of alkynoates and also represents a strategy of direct decarboxylation of esters.

Title compounds are synthesized via Mannich addition reaction of chiral trifluoroacetaldimine and lithium enolates of alkyl acetates.

CO2 capture science and technology, particularly for the post-combustion CO2 capture, has become one of very important research fields, due to great concern of global warming. Metal–organic frameworks (MOFs) with a unique feature of structural fine-tunability, unlike the traditional porous solid materials, can provide many and powerful platforms to explore high-performance adsorbents for post-combustion CO2 capture. Until now, several strategies for finely tuning MOF structures have been developed, in which either the larger quadrupole moment and polarizability of CO2 are considered: metal ion change (I), functional groups attachment (II) and functional group insertion (III), vary the electronic nature of the pore surface; or targeting the smaller kinetic diameter of CO2 over N2 is focused on: framework interpenetration (IV), ligand shortening (V) and coordination site shifting (VI) contract the pore size of frameworks to improve their CO2 capture properties. In this review, from the viewpoint of synthetic materials scientists/chemists, we would like to introduce and summarize these strategies based upon recent work published by other groups and ourselves.

A versatile metal-free synthesis of allylic N-heterocycles has been developed using a TBAI/TBHP oxidation system. This general protocol could be applied for the C–N bond formation of electron-deficient phthalimides, imidazoles, triazoles, and sulfonamides with cyclic and acylic olefins. The practical use of the method is demonstrated by the amidation of functionalized biologically active substrates.

A DBU-promoted cascade functionalization of a C(sp3)–H bond adjacent to oxygen and a radical cyclization reaction of vinyl isocyanides were developed. The reaction was carried out without the use of any metal catalysts or photoredox catalysis, which provides easy access to multi-functionalized isoquinolines.

involving a C(sp3)-H bond cleavage, oxyalkylation of the double bond, and intramolecular cyclization

Depending on the substitution patterns substrates, either thiazoles or thiazolines are obtained.

A simple procedure is elaborated for the synthesis of α-fluoro-β-keto-amines (III) and (VI) by detrifluoroacetylative Mannich reaction of keto-hydrates (I) and (V) with imines (II).

Reaction of 2-fluoro-1,3-diketone hydrates (I), (IV), and (VI) with aldehydes proceeds through a detrifluoroacetylative aldol addition mechanism to yield fluorinated aldol products in good stereoselectivities.

Multisubstituted dihydropyridines (III) are efficiently obtained from methyl propiolate (II) and propargylamines (I) with high regioselectivity.

Herein is reported a study of asymmetric decarboxylative Mannich addition reactions between (Ss)-N-t-butylsulfinyl-3,3,3-trifluoroacetaldimine and Schiff bases derived from various aldehydes and lithium 2,2-diphenylglycinate. These reactions proceed with excellent diastereoselectivities and good chemical yields, providing a practical method for preparation of trifluoromethyl-containing vicinal diamines. The procedures can be conducted under convenient conditions, rendering this approach of high synthetic value.

The reaction tolerates a broad scope of alkyl and aryl substituted β-keto acid substrates and proceeds with excellent yields and diastereoselectivities.

Amidophenanthridines are prepared from isocyanobiphenyls and amides via oxidative radical C—H bond functionalization and cyclization using tert-butyl peroxybenzoate as oxidant.

Primary and secondary alcohols as well as cyclic ethers add regioselectively to the double bond of N-allyl and N-homoallyl amides.

Oxidative sulfenylation of N-methyl amides with arenesulfonic acid hydrazides yields the corresponding N-sulfenylmethyl amides.

Functionalization of the pyrrole ring using imine (II) as reagent takes place at position 3 of indoles (I) under Friedel—Crafts conditions, whereas position 2 of N-protected indoles (IV) is substituted in the presence of LDA.

A highly diastereoselective synthesis of a previously unknown type of aminobenzothiazol derivatives of high pharmaceutical potential is given.

An oxidative C(sp3)–H bond functionalization of alkanes and alkylation-initiated radical 1,2-aryl migration in α,α-diaryl allylic alcohols using di-tert-butyl peroxide (DTBP) as the oxidant was established, which tolerates a wide range of simple alkane substrates and α,α-diaryl allylic alcohols for direct preparation of α-aryl-β-alkylated carbonyl ketones.

This isocyanide thiolation/intramolecular radical aromatic cyclization sequence tolerates various functional groups and gives good to excellent yields.

The required imines may be prepared in situ, thus affording the products in a sequential three-component reaction.

A metal-free oxidative C(sp3)–H bond functionalization and subsequent conjugate addition reaction using di-tert-butyl peroxide (DTBP) as the oxidant was established, which tolerates a wide range of simple alkane substrates to react with different substituted chromones for direct preparation of 2-alkylchromanones.

The synthesis of a novel type of fluorinated sulfonamides with high pharmaceutical potential can be scaled up.

Enolates of indolin-2-ones react cleanly with the chiral imine (II) to afford adducts (III) and (V) in good diastereoselectivity.

CF3-containing chiral imines readily react with α,α-difluoroenolates affording a novel type of β-keto-amino compounds featuring the R-CO-CF2-CH(NH2)-CF3 moiety. The reactions feature exceptional generality allowing preparation of various aromatic, hetero-aromatic and aliphatic derivatives in high yields and diastereoselectivity. The products are configurationally stable and can be transformed to more functionalized complex compounds.

Here we describe the first attempts to scale up five addition reactions between (SS)-N-tert-butanesulfinyl-(3,3,3)-trifluoroacetaldimine 6 with C-nucleophiles derived from ketones (two examples), glycine Schiff base and heterocycles (two examples). In all cases studied, the observed stereochemical outcome of the scaled up (5.0–25.0 mmol) reactions was lower as compared with the original 0.5 mmol scale. However, the observed worsening of yields and diastereoselectivity was not identical and depended on the reaction conditions and reaction mechanisms. In general, scaling up of the reactions conducted at ambient temperatures presented no problems while the low-temperature (−78 °C) processes would require special equipment to provide strict maintenance of the reaction temperature to obtain the desirable outcome. Importantly, using procedures described here, series of biologically relevant compounds containing 2,2,2-trifluoro-1-(amino)ethyl [CF3 CH(NH2)-] pharmacophore unit can be prepared in enantiomerically pure form on up to 5 g scale, allowing their systematic biological studies.

The main feature of the synthesis of unexpected bis(benzothiazolyl)ethanes is the unusual role of CF3-imine, which serves as a precursor to the bridging ethylene moiety.

Compound (IIIa) can be further transformed to the corresponding β-amino alcohol by stereoselective reduction of its ketone moiety.

Heck reaction catalyzed by Ni(II) containing N-(4,5-dihydrooxazol-2-yl) benzamide has been developed. The coupling of alkenes with aryl iodide or aryl bromide in the presence of potassium carbonate in DMF provides the corresponding products with moderate to good yields. This method possesses obvious advantages such as low-cost catalyst and simple experimental operation. Copyright © 2014 John Wiley & Sons, Ltd.

We demonstrate that reactions between various 1-indanones and (SS)-N-tert-butanesulfinyl-(3,3,3)-trifluoroacetaldimine, conducted in the presence of catalytic amounts of LDA, occur with virtually complete stereochemical outcome, offering reliable and generalized access to biologically relevant β-trifluoromethyl-β-amino indanone derivatives. The products can be isolated in diastereomerically pure form simply by washing the crude reaction mixture with hexanes, underscoring practicality of the present method.

Efficient asymmetric Mannich addition reactions between α,β-unsaturated ketone derived enolates and N -phosphonyl imines were reported. These reactions could proceed smoothly for a variety of imine substrates with good (up to 96%) chemical yields and excellent diastereoselectivities (up to 98:2 dr). The method reported in this work provides an easy access to chiral β′-amino-α,β-enones.

Intermolecular competing kinetic isotope effect experiments indicate, that C(sp3)—H bond cleavage may be the rate-determining step of this cross dehydrogenative coupling reaction.

Transformation of (I) with phenyl or trimethylsilylacetylene, respectively, leads to propargylamine intermediates instead of the desired imidazolidines.

The asymmetric Mannich-type addition between C5-lithiated heterocycles (I) and enantiopure aldimine (II) is described.

2-Methylenecyclobutanones (2-MCBones), used to be difficult to access, but can now be easily achieved by a green and stereospecific Ca(OH)2-catalyzed direct and simple aldol condensation of cyclobutanone and aldehydes under mild conditions. The obtained (E)-2-MCBones should be a class of potentially useful building blocks in synthesis as they could readily undergo an interesting (PhSe)2-catalyzed Baeyer–Villiger (BV) oxidation with H2O2 at room temperature to give the versatile 4-methylenebutanolides. Mechanistic studies revealed that the BV reaction most possibly proceeded via the initial formation of benzeneseleninoperoxoic anhydride [PhSe(O)O]2O, which then converted to benzeneseleninoperoxoic acid PhSe(O)OOH as the active oxidant, followed by its selective addition to the CO bond of 2-MCBones and then a selective C–C bond cleavage and rearrangement to give 4-methylenebutanolides.

The reaction tolerates a wide range of aromatic and heteroaromatic aldehydes but fails with aliphatic octanal.

In the title reaction, the N-tert-butylsulfinyl group serves not only as an efficient chiral auxiliary, but also as an amine protecting group.

An efficient Fe(acac)3-catalyzed decarboxylative C(sp2)–C(sp3) coupling reaction via oxidation of C–H bond adjacent to an oxygen atom has been developed successfully, in which cyclic ethers are selectively transformed into the corresponding alkenylation products with good chemical yields and excellent stereoselectivities. The mechanism was studied and the reaction was supposed to proceed through a radical oxidative coupling process.