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Chemical recycling of polymers to monomers presents a promising solution to the escalating crisis associated with plastic waste. Despite considerable progress made in this field, the primary efforts have been focused on redesigning new monomers to produce readily recyclable polymers. In contrast, limited research into the potential of seemingly "non‐polymerizable" monomers has been conducted. Herein, we propose a paradigm that leverages a "chaperone"‐assisted strategy to establish closed‐loop circularity for a "non‐polymerizable" α, β‐conjugated lactone, 5,6‐dihydro‐2H‐pyran‐2‐one (DPO). The resulting PDPO, a structural analogue of poly(δ‐valerolactone) (PVL), exhibits enhanced thermal properties with a melting point (Tm) of 114 °C and a decomposition temperature (Td,5%) of 305 °C. Notably, owing to the structural similarity between DPO and δ‐VL, the copolymerization generates semi‐crystalline P(DPO‐co‐VL)s irrespective of the DPO incorporation ratio. Intriguingly, the inherent C=C bonds in P(DPO‐co‐VL)s enable their convenient post‐functionalization via Michael‐addition reaction. Lastly, PDPO was demonstrated to be chemically recyclable via ring‐closing metathesis (RCM), representing a significant step towards the pursuit of enabling the closed‐loop circularity of "non‐polymerizable" lactones without altering the ultimate polymer structure. [ABSTRACT FROM AUTHOR]

Nitrile compounds containing ester and amide groups are important functionalized chemicals in synthetic and medicinal chemistry. In this article, an efficient and convenient palladium‐catalyzed carbonylative procedure toward 2‐cyano‐N‐acetamide and 2‐cyanoacetate compounds has been developed. The reaction proceeds under mild conditions via radical intermediate which is suitable for late‐stage functionalization. Gram‐scale experiment was performed successfully under low catalyst loading and gave the target product in excellent yield. Additionally, this transformation can be performed under atmospheric pressure and provide alternative routes to 7 drug precursors. [ABSTRACT FROM AUTHOR]

CuH and CuBpin are versatile catalysts and intermediates in organic chemistry. However, studies that involve both CuH and CuBpin in the same reaction is still rarely reported due to their high reactivity. Now, a study on CuH‐ and CuBpin‐catalyzed borylative methylation of alkyl iodides with CO as the C1 source is reported. Various one carbon prolongated alkyl boranes (RCH2Bpin and RCH(Bpin)2) were produced in moderate to good yields from the corresponding alkyl iodides (RI). In this cooperative system, CuH reacts with alkyl iodide faster than CuBpin. [ABSTRACT FROM AUTHOR]

Regioselective transformation is among the long‐standing challenges in organic synthesis. In this communication, a copper‐catalyzed selectivity controlled regiodivergent borocarbonylation of imines with alkyl iodides has been developed. Various α‐amino ketones and α‐boryl amides were produced in moderate to good yields from the same substrates. The choice of the ligand is key for the regioselectivity control: α‐amino ketones were produced selectively in good yields with (p‐CF3C6H4)3P as the ligand, whereas the corresponding α‐boryl amides were obtained with high regioselectivities when using MeIMes as the ligand. [ABSTRACT FROM AUTHOR]

Multicomponent reactions, particularly those entailing four or more reagents, have presented a longstanding challenge due to the inherent complexities associated with balancing reactivity, selectivity, and compatibility. In this study, we describe a palladium‐catalyzed multi‐component fluoroalkylative carbonylation of 1,3‐enynes. A series of products featuring three active functional groups‐allene, fluoroalkyl, and carboxyl, were efficiently and selectively integrated in a single chemical operation. Furthermore, more intricate fluoroalkyl‐substituted pyrimidinones can be constructed by simply altering the 1,3‐bisnucleophilic reagent. This approach also provides a valuable strategy for the late‐stage modification of naturally occurring molecules and concise construction of diverse cyclic compounds. [ABSTRACT FROM AUTHOR]

Organoboron compounds are among the most versatile and useful building blocks in modern synthetic chemistry. The past decades have seen impressive developments in the direct C−H bond borylation of (hetero)arenes in which the applied catalysts are shifting from noble metals to metal‐free systems. This Highlight gives a brief summary on this evolution and focuses on recent elegant work in this field. [ABSTRACT FROM AUTHOR]

Abstract: The development of highly selective procedures is one of the core goals in organic chemistry. Among the known organic transformations, carbonylation reactions present an ideal choice for the preparation of carbonyl‐containing compounds. In this review, the recent achievements on the control of the selectivity for carbonylation reactions have been summarized. The effects of ligands, solvents, and bases on the selectivity are been discussed. [ABSTRACT FROM AUTHOR]

The reactivity of the heteronuclear oxide cluster [Ga2Mg2O5].+, bearing an unpaired electron at a bridging oxygen atom (Ob.−), towards methane and ethane has been studied using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). Hydrogen-atom transfer (HAT) from both methane and ethane to the cluster ion is identified experimentally. The reaction mechanisms of these reactions are elucidated by state-of-the-art quantum chemical calculations. The roles of spin density and charge distributions in HAT processes, as revealed by theory, not only deepen our mechanistic understanding of CH bond activation but also provide important guidance for the rational design of catalysts by pointing to the particular role of doping effects. [ABSTRACT FROM AUTHOR]

Boroaminomethylation of olefins is an efficient process to convert hydrocarbons directly into boron‐, nitrogen‐containing molecules. Such chemicals are a good handle for obtaining more complexed amine derivatives through the various transformations of organoboron. However, using simple and easily available CO as the C1 feedstock to achieve boroaminomethylation is still elusive. Here we report a copper‐catalyzed boroaminomethylation of olefins with CO as the C1 source via the mechanism of a carbene insertion into the N−H bond. This method affords valuable γ‐boryl amines from four inexpensive readily chemicals. The wide synthetic transformations of the γ‐boryl amines demonstrates their utility. Notably, 13C labeling studies revealed that the −CH2‐building block was derived from one molecule of CO. [ABSTRACT FROM AUTHOR]

A CO surrogate: In two recent studies, CO2 has not only been applied as a CO source in the hydroformylation of alkenes and the carbonylative Hiyama–Denmark coupling of aryl iodides, but more interestingly it also attenuates or improves the reactivity of the reactants. [ABSTRACT FROM AUTHOR]

Single, double, triple: Highly selective double H atom abstraction (HAA) from ethane and triple HAA from n‐butane by AuNbO3+ clusters have been characterized by mass spectrometry and DFT calculations. The multiple HAAs are initiated by oxygen‐centered radicals and promoted by gold. The gold atoms act as electron acceptors during the triple HAAs and help to store a pair of valence electrons between Au and Nb atoms (see picture). [ABSTRACT FROM AUTHOR]

Ethers are of central importance in the fields of biomass, energy, and organic chemistry. Herein, a novel cobalt‐catalyzed carbonylative coupling of ethers with amines to construct α‐carbonylated ethers has been achieved. Remarkably, Alfuzosin, a medicine for treatment of benign prostatic hyperplasia (BPH), can be synthesized by this process straightforwardly. Notably, this protocol presents the first example on the direct carbonylative reaction of ethers. [ABSTRACT FROM AUTHOR]

Controllable production of α‐keto amides and amides from the same substrates is an attractive goal in the field of transition‐metal‐catalyzed (double‐)carbonylation. Herein, a novel copper‐catalyzed highly selective double carbonylation of alkyl bromides has been developed. Moderate to good yields of α‐keto amides were obtained as the only products. In the case of alkyl iodides, double‐ and mono‐carbonylation can be achieved controllably under different conditions. [ABSTRACT FROM AUTHOR]

A novel copper‐catalyzed carbonylative trifluoromethylation of unactivated alkenes has been developed. A broad range of β‐trifluoromethylated carboxylic acid derivatives were prepared in moderate to excellent yields from simple alkenes with excellent regioselectivity. It is noteworthy that ethylene gas, as the simplest olefin, can also be applied directly to obtain β‐trifluoromethylated amides and ester. This transformation presents the first example on carbonylative trifluoromethylation of alkenes. [ABSTRACT FROM AUTHOR]

Transition‐metal‐catalyzed multi‐component carbonylation represents an efficient strategy for the preparation of various functionalized carbonyl‐containing compounds. Herein, we report a general palladium‐catalyzed perfluoroalkylative carbonylation of unactivated alkenes using inexpensive and readily available carbon monoxide as the C1 source and perfluoroalkyl halides as the coupling partner. A wide range of phenols and alcohols were transformed into the corresponding β‐perfluoroalkyl esters in high yields with broad functional group tolerance and good chemoselectivity. Additionally, alkyl halides can be utilized as alkoxy source as well to give the desired esters. Moreover, several pharmaceutical and bio‐active molecules were also suitable substrates for this one‐pot multi‐component carbonylation process to give the targeted products in good yields. [ABSTRACT FROM AUTHOR]

Thiocarbonylation of alkynes offers an ideal procedure for the synthesis of unsaturated thioesters. A robust ligand‐controlled regioselective thiocarbonylation of alkynes is developed. Utilizing boronic acid and 5‐chlorosalicylic acid as the acid additive to in situ form 5‐chloroborosalicylic acid (5‐Cl‐BSA), and bis(2‐diphenylphosphinophenyl)ether (DPEphos) as the ligand, linear α,β‐unsaturated thioesters were produced in a straightforward manner. Switching the ligand to tri(2‐furyl)phosphine can turn the reaction selectivity to give branched products. Remarkably, this approach also represents the first example on thiocarbonylation of internal alkynes. [ABSTRACT FROM AUTHOR]

Given the prevalence of amide backbones in marketed pharmaceuticals and their ubiquity as critical binding units in natural peptides and proteins, it remains important to develop novel methods to construct amide bonds. We report here a general method for the anti‐Markovnikov hydroaminocarbonylation of unactivated alkenes under mild conditions, using copper catalysis in combination with hydroxylamine electrophile reagents and poly(methylhydrosiloxane) (PMHS) as a cheap and environmentally friendly hydride source. The reaction tolerates a variety of functional groups and efficiently converts unactivated terminal alkenes, 1,1‐disubstituted alkenes, and cyclic alkenes to the corresponding amides with exclusive anti‐Markovnikov selectivity (and high enantioselectivities/diastereoselectivities). Additionally, with minimal modification of the reaction conditions, alkynes can also undergo tandem hydrogenation‐hydroaminocarbonylation to alkyl amides. [ABSTRACT FROM AUTHOR]

The cover page of the journal "Angewandte Chemie International Edition" is presented.

Herein, we developed a new procedure on 1,2‐dicarbonylative cyclization of 4‐aryl‐1‐butenes with alkyl bromides. Using simple copper catalyst, two molecules of carbon monoxide were introduced into the double bond with the formation of four new C−C bonds and a new ring. Various α‐tetralones and 2,3‐dihydroquinolin‐4‐ones were formed in moderate to good yields. [ABSTRACT FROM AUTHOR]

Transition metal‐catalyzed carbonylative cross‐coupling reactions are some of the most widely used methods in organic synthesis. However, despite the obvious advantages of iron as an abundant and low toxicity transition metal catalyst, its practical application in carbonylation reaction remains largely unexplored. Here we report our recent study on Fe‐catalyzed alkoxycarbonylation of alkyl halides. Mechanistic studies indicate that the reaction is catalyzed by an in situ generated Fe2− complex. This low‐valent iron species activates alkyl bromides via a distinctive two‐electron transfer (TET) process, whereas it proceeds via a single electron transfer (SET) process for alkyl iodides which is consistent with literature. [ABSTRACT FROM AUTHOR]

A convenient and rapid detection method for methanol in ethanol remains a major challenge due to their indistinguishable physical properties. Herein, a novel fluorescence probe based on perovskite was successfully designed to overcome this bottleneck. We report a new zero‐dimensional (0D) hybrid perovskite of [MP]2InxSb1−xCl7 ⋅ 6 H2O (MP=2‐methylpiperazine) displaying an unusual green light emission with near‐unity photoluminescence quantum yield. Remarkably, this 0D perovskite exhibits reversible methanol‐response luminescence switching between green and yellow color but fail in any other organic vapors. Even for blended alcohol solutions, the luminescent probe exhibits excellent sensing performance with multiple superiorities of rapid response time (30 s) and ultra‐low detection limit (40 ppm), etc. Therefore, this 0D perovskite can be utilized as a perfect fluorescence probe to detect traces of methanol from ethanol with ultrahigh sensitivity, selectivity and repeatability. To the best of our knowledge, this work represents the first perovskite as fluorescence probe for methanol with wide potential in environmental monitoring and methanol detection, etc. [ABSTRACT FROM AUTHOR]

Multi‐component carbonylation of olefins, a reaction that installs both a carbon–carbon(heteroatom) bond and a carbonyl group across the double bond, is an attractive strategy for alkene functionalization. Herein, we developed a novel nickel‐catalyzed four‐component carbonylation of olefins with ethers under low CO gas pressure. Using alcohols and amines as the reaction partner, diverse γ‐oxy‐substituted esters and amides were produced in good yields with excellent functional group tolerance. Notably, Naftidrofuryl, a medicine for the treatment of cerebrovascular disease (CVD), can be synthesized by this process straightforwardly. [ABSTRACT FROM AUTHOR]

The lithium bis(imino)stannylenoid (NIPr)2Sn(Li)Cl ( 1; NIPr=bis(2,6-di isopropylphenyl)imidazolin-2-imino) was prepared by the reaction of LiNIPr with 0.5 equiv of SnCl2⋅diox (diox=1,4-dioxane) and the ambiphilic character of the compound was demonstrated by investigations into its reactivity. Treatment of 1 with I2 or MeI yielded the oxidative addition products (NIPr)2SnI2 and (NIPr)2Sn(Me)I, respectively. In contrast, the reaction of 1 with one equivalent of Me3SiCl resulted in the formation of Me3SiNIPr and the chlorostannylene dimer [NIPrSnCl]2. Moreover, the substitution reaction of compound 1 with MeLi led to the formation of the methyl-substituted stannate (NIPr)2Sn(Li)Me. [ABSTRACT FROM AUTHOR]

Multicomponent reactions, especially those involving four or even more reagents, have been a long-standing challenge because of the issues associated with balancing reactivity, selectivity, and compatibility. Herein, we demonstrate how the use of a reagent capsule provides straightforward access to synthetically valuable thiochromenone derivatives by a palladium-catalyzed carbonylative four-component reaction. To the best of our knowledge, this is the first example of applying a capsule to prevent catalyst poisoning and undesired side reactions of the multicomponent reaction. [ABSTRACT FROM AUTHOR]

The thermal reactions of the closed-shell, "naked" gold-carbene complex [Au(CH2)]+ with methane have been explored by using FTICR mass spectrometry complemented by quantum chemical (QC) calculations at the CCSD(T)//BMK level of theory. Mechanistic aspects for this unprecedentedly efficient carbene insertion in the CH bond of methane have been addressed and the origin of the counterintuitive high reactivity of [Au(CH2)]+ towards this most inert hydrocarbon is discussed. [ABSTRACT FROM AUTHOR]

Mechanistic insight into the homolytic cleavage of the OH bond of water by the heteronuclear oxide cluster [Ga2Mg2O5].+ has been derived from state-of-the-art gas-phase experiments in conjunction with quantum chemical calculations. Three pathways have been identified computationally. In addition to the conventional hydrogen-atom transfer (HAT) to the radical center of a bridging oxygen atom, two mechanistically distinct proton-coupled electron-transfer (PCET) processes have been identified. The energetically most favored path involves initial coordination of the incoming water ligand to a magnesium atom followed by an intramolecular proton transfer to the lone-pair of the bridging oxygen atom. This step, which is accomplished by an electronic reorganization, generates two structurally equivalent OH groups either of which can be liberated, in agreement with labeling experiments. [ABSTRACT FROM AUTHOR]

Despite rapid progress over the past decade, most polycondensation systems even upon a small structural variation of the building units eventually result in amorphous polymers other than the desired crystalline covalent organic frameworks. This synthetic dilemma is a central and challenging issue of the field. Here we report a novel approach based on module‐patterned polymerization to enable efficient and designed synthesis of crystalline porous polymeric frameworks. This strategy features a wide applicability to allow the use of various knots of different structures, enables polycondensation with diverse linkers, and develops a diversity of novel crystalline 2D polymers and frameworks, as demonstrated by using the C=C bond‐formation polycondensation reaction. The new sp2‐carbon frameworks are highly emissive and enable up‐conversion luminescence, offer low band gap semiconductors with tunable band structures, and achieve ultrahigh charge mobilities close to theoretically predicted maxima. [ABSTRACT FROM AUTHOR]

An unprecedented and challenging defluorinative carbonylation was achieved. Enabled by a Pd/Cu cooperative catalyst system, the first example of defluorinative carbonylative coupling has been established. With gem‐difluoroalkenes and aryl iodides as the substrates, this methodology offers flexible and facile access to privileged α‐fluorochalcones under mild reaction conditions in moderate‐to‐excellent yields. Mechanistic studies indicated transmetalation between palladium and copper intermediates as a crucial step of the catalytic cycle. [ABSTRACT FROM AUTHOR]

Amides are one of the most ubiquitous functional groups in synthetic and medicinal chemistry. Novel and rapid synthesis of amides remains in high demand. In this communication, a general and efficient procedure for branch‐selective hydroamidation of vinylarenes with hydroxyamine derivatives enabled by copper catalysis has been developed for the first time. The reaction proceeds under mild conditions and tolerates a broad range of functional groups. Applying a chiral phosphine ligand, an enantioselective variant of this transformation was achieved, affording a variety of chiral α‐amides with excellent enantioselectivities (up to 99 % ee) and high yields. [ABSTRACT FROM AUTHOR]

We report here a general four‐component synthetic procedure for the preparation of β‐boryl ketones and β‐boryl vinyl esters. Joint catalyzed by palladium and copper catalysts, borocarbonylative reaction between vinylarenes, aryl halides/triflates, B2Pin2, and carbon monoxide proceed successfully. A variety of synthetically useful β‐boryl ketones were synthesized in good to high yields by using aryl iodides as the substrates. It is noteworthy that when aryl triflates were applied as the starting materials, β‐boryl vinyl esters were synthesized in a similar manner and with broad functional group tolerance. A rational mechanism for this reaction was also proposed. [ABSTRACT FROM AUTHOR]

The borocarbonylative coupling of unactivated alkenes with alkyl halides remains a challenge. In this communication, a Cu‐catalyzed borocarbonylative coupling of unactivated alkenes with alkyl halides for the synthesis of β‐boryl ketones has been developed. A broad range of β‐boryl ketone derivatives was prepared in moderate to excellent yields with complete regioselectivity. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescent (TADF) materials generally suffer from severe concentration quenching. Efficient non‐doped TADF emitters are generally highly twisted aromatic amine‐based compounds with isolated chemical moieties. Herein we demonstrate that co‐facial packing and strong π–π intermolecular interactions give rise to bright TADF emissions in non‐doped film and crystalline states within the compound 2,4‐diphenyl‐6‐(thianthren‐1‐yl)‐1,3,5‐triazine (oTE‐DRZ). Quantum chemistry simulations indicate that a disperse outer orbital of sulfur atoms, a folded thianthrene plane (for a reduced donor–acceptor distance), and a triazine acceptor with n–π* character, generate a spatially conjugated transition with a small singlet–triplet splitting energy. In company with a highly emissive non‐doped film, the corresponding organic light‐emitting diode achieved a 20.6 % external quantum efficiency, verifying its potential for high‐performance optoelectronic applications. In a crystalline state, it was verified that intra‐ and intermolecular dual TADF assisted by a hidden room‐temperature phosphorescent state. This state could preserve the long‐lived excitons while suppressing non‐radiation, and it could serve as a "spring‐board" for cascade up‐conversion processes. The oTE‐DRZ crystal showed greenish‐blue emission with a very high photoluminescent quantum yield of approximately 87 %, which is the highest among all TADF crystals reported to date. [ABSTRACT FROM AUTHOR]

A DMAP‐N‐oxide, featuring an α‐amino acid as the chiral source, was developed, synthesized and applied in asymmetric Steglich rearrangement. A series of O‐acylated azlactones afforded C‐acylated azlactones possessing a quaternary stereocenter in high yields (up to 97 % yield) and excellent enantioselectivities (up to 97 % ee). Compared to the widespread use of pyridine nitrogen, which serves as the nucleophilic site in the asymmetric acyl transfer reaction, we discovered that chiral DMAP‐N‐oxides, in which the oxygen now acts as the nucleophilic site, are efficient acyl transfer catalysts. Our finding might open a new door for the development of chiral DMAP‐N‐oxides for asymmetric acyl transfer reactions. A DMAP‐N‐oxide, featuring an α‐amino acid as the chiral source, was developed, synthesized and applied in asymmetric Steglich rearrangement. A series of O‐acylated azlactones afforded C‐acylated azlactones possessing a quaternary stereocenter in high yields (up to 97 % yield) and excellent enantioselectivities (up to 97 % ee). [ABSTRACT FROM AUTHOR]

A novel procedure on the carbonylative synthesis of chromenones has been developed. With simple phenols and internal alkynes as the substrates, various chromenones were isolated in moderate to good yields with excellent regioselectivity and functional-group tolerance by using iridium as the catalyst and copper as the promotor at atmospheric pressure. Notably, this is the first example on carbonylative annulation of simple phenols and alkynes. [ABSTRACT FROM AUTHOR]

Carbonylation reactions are a most powerful method for the synthesis of carbonyl-containing compounds. However, most known carbonylation procedures still require noble-metal catalysts and the use of activated compounds and good nucleophiles as substrates. Herein, we developed a copper-catalyzed carbonylative transformation of cycloalkanes and amides. Imides were prepared in good yields by carbonylation of a C(sp3)−H bond of the cycloalkane with the amides acting as weak nucleophiles. Notably, this is the first report of copper-catalyzed carbonylative C−H activation. [ABSTRACT FROM AUTHOR]

We demonstrate herein a promising pathway towards low-energy CO2 capture and release triggered by UV and visible light. A photosensitive diarylethene ligand was used to construct a photochromic diarylethene metal-organic framework (DMOF). A local photochromic reaction originating from the framework movement induced by the photoswitchable diarylethene unit resulted in record CO2-desorption capacity of 75 % under static irradiation and 76 % under dynamic irradiation. [ABSTRACT FROM AUTHOR]

A new approach for the facile synthesis of fused quinazolinone scaffolds through a palladium-catalyzed carbonylative coupling followed by an intramolecular nucleophilic aromatic substitution is described. The base serves as the key modulator: Whereas DBU gives rise to the linear isomers, Et3N promotes the preferential formation of angular products. Interestingly, a light-induced 4+4 reaction of the product was also observed. [ABSTRACT FROM AUTHOR]

After decades of development, carbonylation reactions have become one of the most powerful tools in modern organic synthesis. However, the requirement of CO gas limits the applications of such reactions. Reported herein is a versatile and practical protocol for carbonylative reactions which rely on the cooperation of phenyl formate and nonaflate, and the generation of CO in situ. This protocol has a high functional-group tolerance and could be applied in carbonylations with C, N, and, O nucleophiles. The corresponding amides, alkynones, furanones, and aryl benzoates were synthesized in good yields. [ABSTRACT FROM AUTHOR]

Given the importance of quinazolinones and carbonylative transformations, a palladium-catalyzed four-component carbonylative coupling system for the synthesis of diverse 4(3 H)-quinazolinone in a concise and convergent fashion has been developed. Starting from 2-bromoanilines (1 mmol), trimethyl orthoformate (2 mmol), and amines (1.1 mmol), under 10 bar of CO, the desired products were isolated in good yields in the presence of Pd(OAc)2 (2 mol %), BuPAd2 (6 mol %) in 1,4-dioxane (2 mL) at 100 °C, using N, N-diisopropylethylamine (2 mmol) as the base. Notably, the process tolerates the presence of various reactive functional groups and is very selective for quinazolinones, and was used in the synthesis of the precursor to the bioactive dihydrorutaempine. [ABSTRACT FROM AUTHOR]