We have quantum chemically explored the competition between the SN2 and SN2′ pathways for X– + H2C═CHCH2Y (X, Y = F, Cl, Br, I) using a combined relativistic density functional theory and coupled-cluster theory approach. Bimolecular nucleophilic substitution reactions at allylic systems, i.e., Cγ═Cβ–Cα–Y, bearing a leaving-group at the α-position, proceed either via a direct attack at the α-carbon

A versatile synthesis of α-amino bisphosphonates has been achieved through one-pot interrupted Ritter-type reaction under mild conditions. The reactive Ritter intermediate nitrilium is in situ generated by treatment of nitrile with readily accessible Tf2O/HC(OR1)3, which is trapped by phosphite ester to deliver the desired product. This protocol is efficient, scalable, and well compatible with a broad

The stereoselective introduction of glycosidic bonds is of paramount importance to oligosaccharide synthesis. Among the various chemical strategies to steer stereoselectivity, participation by either neighboring or distal acyl groups is used particularly often. Recently, the use of the 2,2-dimethyl-2-(ortho-nitrophenyl)acetyl (DMNPA) protection group was shown to offer enhanced stereoselective steering

The Cu(I)-catalyzed reaction between five-, six-, seven-, and eight-membered cyclic 1-bromoallyl tosylates and five- and six-membered cyclic 1,3-dicarbonyls in DMF at 80 °C using Cs2CO3 as a base and 2-picolinic acid as an additive selectively delivers a wide array of bisannulated 4H-pyrans in a single step with yields up to 92%. The transformations are considered to proceed as intermolecular C-al

C(aryl)–OMe bond functionalization catalyzed by cobalt(II) chloride in combination with a nacnac-type ligand and magnesium as a reductant is reported. Borylation and benzoylation of aryl methoxides are demonstrated, and C(aryl)–SMe bond borylation can be achieved under similar conditions. This is the first example of achieving these transformations using cobalt catalysis. Mechanistic studies suggest

An efficient and novel approach to accessing 3-selenylquinolines from diaryl diselenides and acyclic, selenium-free substrates is described. Preliminary mechanistic studies indicate that the combination of CuCl2 and air affords an appropriate environment for producing arylselenyl radicals that initiate the cascade cyclization of N-(2-alkynyl)anilines, forming key Se–C and C–C bonds in a single step

A nickel-catalyzed tandem Ueno–Stork cyclization is developed to enable stereoselective 1,2-dicarbofunctionalization of cyclic alkenes and efficiently build various bicyclic products. This new protocol does not involve any toxic or difficult-to-remove tin reagent and is scalable and amenable to build all-carbon quaternary centers.

Brønsted acid- and/or Lewis acid-catalyzed selective C3-allylation and formal [3 + 2]-annulation of spiro-aziridine oxindoles with allylsilanes have been demonstrated to deliver direct access to 3-allyl-3-aminomethyl oxindoles and 5-silyl methyl spiro[pyrrolidine-3,3′-oxindoles], respectively. The acid-catalyzed methods do not provide any stereoselectivity when chiral spiroaziridines are used. However

A novel strategy for the synthesis of 1-pyrrolines based on formal [4 + 1] annulation of 2-alkyl-2H-azirines with diazocarbonyl compounds has been developed. This one-pot approach includes the Rh(II)-catalyzed formation of 4-alkyl-2-azabuta-1,3-dienes, followed by the DBU-promoted cyclization, and features a good substrate tolerance. The 1-pyrrolines containing an ester group at the C3 were prepared

Chiral bicyclic N,O-acetal isoserine derivatives have been synthesized by an acid-catalyzed tandem N,O-acetalization/intramolecular transcarbamoylation reaction between conveniently protected l-isoserine and 2,2,3,3-tetramethoxybutane. The delicate balance of the steric interactions between the different functional groups on each possible diastereoisomer controls their thermodynamic stability and hence

Aza-helicenes are one of the most important series of heterohelicenes; herein, a series of novel aza-helicenes (5H, 6H, 6S, and 8S) were prepared via Bischler–Napieralski cyclization, and the interconversion dynamic process of these aza-helicenes was revealed using density functional theory calculations. The novel nitrogen-doped [6]helicene (6H) possesses a very high interconversion energy barrier

A novel one-pot reaction of anilines with acetylenedicarboxylate diesters in the presence of boron trifluoride, iodine, and trifluoroacetic acid or methylsulfonic acid has been developed under solvent-free ball-milling conditions, affording a variety of polysubstituted 1,2-dihydroquinolines bearing multiple ester groups in moderate to excellent yields. The present protocol features mild reaction conditions

Here, we report a novel and facile protocol for the synthesis of benz[c,d]indol-2-imines via palladium-catalyzed C–C and C–N coupling of 8-halo-1-naphthylamines with isocyanides in a single step. The reaction features broad substrate scopes and mild conditions, providing an efficient alternative for the construction of antiproliferative agents and BET bromodomain inhibitors. If 0.1 mL of H2O was added

An efficient and convenient method to synthesize 6-oxyalkylated 1,2,4-triazine-3,5(2H, 4H)-diones has been developed via visible-light-induced cross-dehydrogenative coupling reaction between 1,2,4-triazine-3,5(2H, 4H)-diones and ethers with a wide range of functional group tolerance. The present transformation employs the cheap and low-toxic 2-tert-butylanthraquinone as a metal-free photocatalyst and

An Fe(OTf)2-catalyzed three-component coupling reaction of α,β,γ,δ-unsaturated carbonyl compounds with alkylsilyl peroxides in the presence of certain heteronucleophiles (ROH and indole) is realized under mild reaction conditions. A variety of α,β,γ,δ-diene carbonyl substrates with different substituents were successfully employable via combination with several different alkylsilyl peroxides. This

Hydrogen bonds not only play a crucial role in the life sciences but also endow molecules with fantastic physical and chemical properties, which help in the realization of their high-tech applications. This work presents an efficient strategy for achieving highly efficient solid-state dual-emission blue emitters with mechanical force-induced enhanced emission properties via intermolecular hydrogen

Macrocyclic glycoazobenzenes, as an emerging class of photoswitchable chiral macrocyclic compounds, have shown interesting properties since their discovery in 2017. We have recently employed the azobenzene-ester-linked glycosyl donor–acceptor pairs to study the influence of photoisomerization on intramolecular glycosylation. To continue the investigation on the stereoselectivity aspect of glycosylation

A visible-light-driven organophotocatalyzed multicomponent approach has been developed for tandem direct C(sp3)–H activation and alkylation followed by trifluoromethylthiolation in a one-pot operation. We report a completely metal-free, tandem, three-component approach for the difunctionalization of activated alkenes via the photoinduced radical pathway. This protocol allows the formation of two new

DU8ML, a fast and accurate machine learning-augmented density functional theory (DFT) method for computing nuclear magnetic resonance (NMR) spectra, proved effective for high-throughput revision of misassigned natural products. In this paper, we disclose another important aspect of its application: correction of unusual reaction mechanisms originally proposed because of incorrect product structures

The use of water in organic synthesis draws attention to its green chemistry features and its unique ability to unveil unconventional reactivities. Herein, literature about the use of water as a reaction medium under visible-light photocatalytic conditions is summarized in order to highlight challenges and opportunities. Accordingly, this Synopsis has been divided into four different sections focused

The base n-BuLi with sparteine allows a kinetic resolution of N-Boc-2-aryl-4-methylenepiperidines. The 2,2-disubstituted products and recovered starting materials were isolated with high enantiomeric ratios. From VT-NMR spectroscopy and DFT studies, the rate of rotation of the N-Boc group is fast. Lithiation and trapping of the enantioenriched starting materials gave 2,2-disubstituted piperidines with

Miniaturization offered by microreactors provides for superb reaction control as well as excellent heat and mass transfer. By performing chemical reactions in microreactors or tubular systems under continuous flow conditions, increased safety can be harnessed which allows exploitation of these technologies for the generation and immediate consumption of high-energy intermediates. This Synopsis demonstrates

The asymmetric synthesis of novel 3-substituted isoindolinones is herein reported. A new cascade reaction was developed that consisted of the asymmetric nitro-Mannich reaction of suitable α-amido sulfones designed from 2-formyl benzoates, followed by the in situ cyclization of the adducts. Very high enantioselectivities, up to 98% ee, and very good yields were obtained in the presence of the readily