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Multifunctional energy storage and conversion devices that incorporate novel features and functions in intelligent and interactive modes, represent a radical advance in consumer products, such as wearable electronics, healthcare devices, artificial intelligence, electric vehicles, smart household, and space satellites, etc. Here, smart energy devices are defined to be energy devices that are responsive to changes in configurational integrity, voltage, mechanical deformation, light, and temperature, called self-healability, electrochromism, shape memory, photodetection, and thermal responsivity. Advisable materials, device designs, and performances are crucial for the development of energy electronics endowed with these smart functions. Integrating these smart functions in energy storage and conversion devices gives rise to great challenges from the viewpoint of both understanding the fundamental mechanisms and practical implementation. Current state-of-art examples of these smart multifunctional energy devices, pertinent to materials, fabrication strategies, and performances, are highlighted. In addition, current challenges and potential solutions from materials synthesis to device performances are discussed. Finally, some important directions in this fast developing field are considered to further expand their application.

A carbene-catalyzed desymmetrization of prochiral bisphenol compounds bearing remote P-stereogenic centers is disclosed. The catalytic reactions can be performed on gram scales with 1 mol % N-heterocyclic carbene (NHC) catalyst, providing efficient access to enantiomerically enriched P-stereogenic phosphinates. The chiral phosphinates prepared with our method can find widespread applications as asymmetric organic catalysts and ligands.

We present here an unprecedented cobalt-catalyzed enantioselective vinylation of α-ketoesters, isatins, and imines to deliver a range of synthetically useful allylic alcohols and amines in high enantiopurity. This method employs commercially available and easy to handle catalysts and reagents and exhibits a high degree of practicality. The efficiency, selectivity, and operational simplicity of this catalytic system coupled with the substrate generality render this method a valuable tool in organic synthesis.

A cascade C–H functionalization/amidation reaction of aminobiaryls with diazomalonates has been developed under rhodium catalysis, affording new azepinone derivatives in moderate to excellent yields.

Polypyrrole (PPy), as one of the conducting polymers, has emerged as a promising active material for high performance supercapacitor owing to its intrinsic characteristics ( e.g. high electrical conductivity and interesting redox properties). It’s attracting more and more attentions with the development of flexible/wearable devices thanks to the great flexibility and ductility of PPy as a polymer. This review presents a comprehensive understanding on synthesis, morphology control, electrochemical performances and solid-state devices of the nanostructured PPy and its nanocomposites. In the past decades, a variety of nanostructures, including one-, two-, and three-dimensional, have been designed and fabricated via different methods, demonstrating a great potential for the application as supercapacitor electrodes. Thereafter, many nanostructured PPy-based supercapacitors with different macroscopic configurations have been presented aiming to achieve better electrochemical performance, and some representative ones, for example, flexible and/or wearable supercapacitors, are summarized in this review. Cycling stability is another critical issue that determines its practicability of the PPy-based devices. Solutions to improve cycling performance and mechanisms behind are also discussed. Last, perspectives for the future development in nanostructured PPy-based supercapacitors are described. This review gives a summary of selected contributions which we hope to provide readers with a better understanding of the fast developing field of PPy-based supercapacitors.

A new and efficient approach for the synthesis of oxygen and nitrogen heterocycles by organoselenium catalysis has been developed. The exo-cyclization proceeded smoothly under mild conditions with good functional group tolerance and excellent regioselectivity. Mechanistic studies revealed that 1-fluoropyridinium triflate is key for oxidative cyclization.

A nonmetal-catalyzed process for the synthesis of polysubstituted oxazoles from inexpensive and readily available α-amino acids and methyl ketones is established. This reaction is proposed to achieve oxidative cleavage of C(sp3)–H bonds, followed by decarboxylation and annulation. The mild reaction conditions employed in both cases enable the tolerance of a wide range of functional groups as well as high reaction efficiency.

The first total synthesis of the alkaloid (−)-haliclonin A is reported. The asymmetric synthesis relied on a novel organocatalytic asymmetric conjugate addition of nitromethane with 3-alkenyl cyclohex-2-enone to set the stereochemistry of the all-carbon quaternary stereogenic center. The synthesis also features a Pd-promoted cyclization to form the 3-azabicyclo[3,3,1]nonane core, a SmI2-mediated intermolecular reductive coupling of enone with aldehyde to form the requisite secondary chiral alcohol, ring-closing alkene and alkyne metathesis reactions to build the two aza-macrocyclic ring systems, and an unprecedented direct transformation of enol into enone.

Single crystals of the new sulfides FeV4S8 (I) and KFe2V8S16 (II) are prepared via a melting salt method using, Fe, V, S, K2S in the case of (II), and KI (evacuated silica tubes, 1073 K, 3 d; cooling to 873 K at a rate of 3 K/h).

Stable β-PdH0.43 nanocrystals are produced by heating a Pd(acac)2 solution in DMF (160 °C, 4 h) using the in situ H2 production from catalytic decomposition of the latter.

Metal–organic frameworks (MOFs), an emerging type of porous crystalline materials, have received increasing attention in recent years due to their compositional, structural and chemical versatility. Moreover, great progress has been made in the fundamental study and technological development of two-dimensional (2D) materials, such as graphene and metal dichalcogenide nanosheets, which exhibit a number of unique and attractive properties for wide applications. Recently, the smart integration of the aforementioned two types of functional materials, i.e. MOFs and 2D materials, has led to improved performance in molecular absorption, separation and storage, and shown promise in selective catalysis and biosensing. This feature article aims at providing a brief introduction to the composites composed of MOFs and 2D materials, focusing mainly on their preparation methods and applications. Finally, technical challenges and future opportunities in this field will also be discussed.

An unprecedented formal hydroallylation of heterobicyclic alkenes is achieved upon treatment with allyltrifluoroborate (II) in the presence of CoBr2 as the catalyst.

Two new pregnane glycosides, hirsutosterosides A and B (1 and 2), as well as two new α-tocopherylhydroquinone glycosides, cladophenol glycosides A and B (3 and 4) were isolated from a soft coral Cladiella hirsuta. In addition, a new steroidal glycoside, lobatasteroside A (5) along with six known steroids (6–11), were discovered from the other soft coral Sinularia nanolobata. Their structures were elucidated by extensive spectroscopic analysis. Cytotoxicities of the isolates against a limited panel of cancer cell lines were reported. The inhibitory activities for superoxide anion generation and elastase release for these compounds were also examined to evaluate the anti-inflammatory potential.

A method for the one-pot synthesis of phenothiazines from benzothiazoles and aryl ortho-dihalides was explored. Preliminary work on the mechanism of the reaction suggested that it follows a domino process, including the hydrolysis of benzothiazoles followed by C–S coupling and C–N coupling. The low loading of the catalyst system (5 mol-% for both copper and ligand), the mild experimental conditions (90 °C, 12 h), and the use of a green reaction medium make this synthesis very attractive to academia and industry.

A highly chemoselective and regioselective dehydrogenative cross-coupling (DCC) reaction of unactivated pyridines with cyclic or acyclic ethers has been developed to give the corresponding 2- or 4-coupled pyridines in satisfactory yields. The DCC reaction affords an efficient and greener synthesis for a range of new pyridines. A possible mechanism involving radical substitution is also proposed.

Compounds (IV), (VII), (IX), and (X) are synthesized by an unconventional hydrothermal route and structurally characterized by single crystal XRD.

A practical and efficient strategy has been described for the preparation of 4-quinolone derivatives. Using commercially available diethyl acetylenedicarboxylate and aromatic amines as starting materials, the synthetic protocol has been achieved and afforded the product via hydroamination at room temperature followed by PPA-catalyzed intramolecular ring closure. The products can be easily obtained in high yields. Conditions and mechanism of the reaction have also been investigated. This protocol is environmentally friendly and transition-metal-free, with advantages including short reaction time, convenient operation, and mild reaction conditions.

Isolation and structural elucidation of norperovskatone (I) and biperovskatone (II) are described.

Phenanthroline ligand-supported copper(I) fluoroalkoxide complexes bearing a trifluoroethoxy, a pentafluoropropoxy or a tetrafluoropropoxy substituent are prepared and applied in the scalable synthesis of fluoroalkyl (hetero)aryl ethers.

The title reaction is promoted by Tf2O and can be viewed as the acrylation of Grignard reagents using amides as stable and selective acylation agents.

A rhodium complex with an amphiphilic, chiral surfactant-type ligand is applied to the asymmetric transfer hydrogenation of long-chained aliphatic ketoesters.

An enantioselective synthesis of the ABC-tricyclic furanochroman core of phomactin A has been accomplished by a γ-hydroxylation approach. The C ring was established by γ-hydroxylation of an α-enone. The regioselectivity was optimized by using a strong base with an oxophilic cation (t-BuLi) and a bulky oxygen donor (Davis reagent), which afforded the γ-hydroxylation product selectively in 63% yield.

Three new phenolic tricyclic diterpenoids including hispidanol A (I) and B (II) are isolated from rhizomes of Isodon hispida together with 14 known compounds.

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

A one-pot reaction for the transformation of common secondary amides into amines with C–C bond formation is described. This method consists of in situ amide activation with Tf2O–partial reduction–addition of C-nucleophiles. The method is general in scope, which allows employing both hard nucleophiles (RMgX, RLi) and soft nucleophiles, as well as enolates. With the use of soft nucleophiles, the reaction proceeded with high chemoselectivity at a secondary amide in the presence of ester, cyano, nitro, and tertiary amide groups.

Three new compounds, atriplicone A (I), B (II), and C (III) are isolated together with five known compounds.

Various N-homoallylic amines are cyclized to functionalized pyrrole structures (mechanism).

Amorphous SiCxOy films are prepared by very high frequency plasma enhanced chemical vapor deposition at 150 °C using a gas mixture of SiH4, CH4, and O2 as the precursor.

The procedure for the preparation of various 2,4-di and 2,4,5-trisubstituted oxazoles is applicable to the synthesis of thiazoles.

An unprecedented catalytic system composed of the Wilkinson catalyst [Rh(PPh3)3Cl] and CF3COOH enabled the highly regioselective cross-coupling of aromatic amines with a variety of heteroarenes through dual CH bond cleavage. This protocol provided a facile and rapid route from readily available substrates to (2-aminophenyl)heteroaryl compounds, which may be conveniently transformed into highly extended π-conjugated heteroacenes. The experimental studies and calculations showed that thianaphtheno[3,2-b]indoles have large HOMO–LUMO energy gaps and low-lying HOMO levels, and could therefore potentially be high-performance organic semiconductors. Herein we report the first use of a rhodium(I) catalyst for oxidative CH/CH coupling reactions. The current innovative catalyst system is much less expensive than [RhCp*Cl2]2/AgSbF6 and could open the door for the application of this approach to other types of CH activation processes.

An efficient method is reported for the copper(I)-catalyzed trifluoromethylthiolation of allylic bromides by using elemental sulfur and CF3SiMe3. This rate of this transformation was significantly accelerated in the presence of 18-crown-6, and the reaction afforded the desired products in moderate to excellent yields with high stereo- and regioselectivity. This method can tolerate a number of functional groups and provides facile access to a variety of allylic trifluoromethyl thioethers. The copper(I)-catalyzed trifluoromethylthiolation of propargylic chlorides was also investigated. A plausible mechanism that involves an allylcopper(III) intermediate is proposed.

A novel facile protocol allows the synthesis of pyrroloisoquinolines from tetrahydroisoquinolines and various dipolarophiles via 1,3-dipolar cycloaddition/oxidation/aromatization cascade.

Optimized conditions are elaborated for a dehydrogenative aminohalogenation in the coupling of aromatic amines with alkenes in the presence of LiBr.

An efficient Pd-catalyzed oxidative cyclization reaction for the synthesis of functionalized indolines by direct C–H activation of acetanilide has been developed. The norbornylpalladium species formed via direct ortho C–H activation of acetanilides is supposed to be a key intermediate in this transformation.

The title compounds show significant growth inhibitory activities against cervical cancer HeLa cells.

A dehydrogenative cross-coupling reaction between allylic C-H bonds and the α-C-H bond of ketones or aldehydes was developed using Cu(OTf)2 as a catalyst and DDQ as an oxidant. This synthetic approach to γ,δ-unsaturated ketones and aldehydes has the advantages of broad scope for both ketones and aldehydes as reactants, mild reaction conditions, good yields and atom economy. A plausible mechanism using Cu(OTf)2 as a Lewis acid catalyst was also proposed (DDQ=2,3-dichloro-5,6-dicyano-1,4-benzoquinone; Tf=trifluoromethanesulfonate).

The first Co/Pd-cocatalyzed intramolecular C-H amination and aziridination reactions were developed. Sulfamate esters were converted to oxathiazinanes by using CoPd(OAc)4 as catalyst and PhI(OAc)2 as oxidant. The mutual presence of both Co and Pd is crucial for the catalytic activity. This combination of two metals with simple acetate ligands provides an economical alternative to the Rh-catalyzed insertion of nitrenoids into C-H bonds.

A novel approach to forge C—N and C—O bonds in one process for the synthesis of trisubstituted oxazole derivatives (III) and (V) is reported.

Efficient preparation of synthetically important CF3-containing α,β-unsaturated esters is described using an NHC-catalyzed multicomponent reaction. This approach combines sequential NHC-mediated HOMO and LUMO activation to produce a C–C bond and C–O bond in a one-pot operation.

A method for preparing multisubstituted N-(tosylamino)pyrrole derivatives through AuCl3-catalyzed cycloisomerization of the β-alkynyl hydrazone compounds was described. The reaction could be carried out in one pot from the β-ketoesters to give the cyclized products in moderate to excellent yields with low catalyst loadings.

A pyridinebis(oxazoline) cobalt complex is a very efficient precatalyst for the hydrosilylation of terminal alkynes with Ph2 SiH2 , providing α-vinylsilanes with high (Markovnikov) regioselectivity and broad functional-group tolerance. The vinylsilane products can be further converted into geminal borosilanes through Markovnikov hydroboration with pinacolborane and a bis(imino)pyridine cobalt catalyst.

The novel and one-pot synthesis of 5-hydroxyl hydantoins from Ugi five-component condensation procedures is reported. The transformation was promoted via a microwave heating method and provided 5-hydroxyl hydantoins in workable yields, representing a direct approach to this synthetically challenging and biologically interesting pharmacophore.

A copper-catalyzed phosphorylation of coumarins has been developed. Different from previous reports, this catalytic system involved the use of copper as a catalyst and trialkyl phosphonates as phosphorus sources with moderate to good yields, which provides an alternative way to prepare coumarins containing phosphates.

Five new altenusin derivatives, compounds 1–5, along with six known analogues 6–11, were isolated from a culture of the endophytic fungus Alternaria sp. SK6YW3L, which was isolated from a fresh fruit of the mangrove plant Sonneratia caseolaris, collected from the South China Sea. Their structures were elucidated by analysis of 1D and 2D NMR and high resolution mass spectroscopic data. The absolute configurations of compounds 1–3 and 5 were assigned by quantum chemical calculations of the electronic circular dichroic (ECD) spectra. Structures of compounds 1 and 4 were further confirmed by single-crystal X-ray diffraction experiments using Cu Kα radiation. All isolated compounds were evaluated for α-glucosidase inhibitory activity, and compounds 2, 3 and 9 exhibited moderate inhibitory activity. The plausible biosynthetic pathways for all the compounds were proposed.

A highly stereoselective sequential annulation reaction between γ-substituted allenoates and ketimines is reported.

The unexpected direct C—H triflylation of styrenes (I) with sodium triflinate (II) affording title compounds (III) is reported.