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Herein, we report a photoinduced 1,7-hydrosulfonylation of allylic ethers and amides via a sequential Pd-mediated 1,5-HAT process and Pd-catalyzed allylic nucleophilic attack of arylsulfonates. This rationally designed synthetic protocol allows for facile construction of a series of structurally novel allylic sulfonated scaffolds, and features mild conditions, cheap and readily available raw materials and functional group compatibility. [ABSTRACT FROM AUTHOR]

Development of a new catalytic and straightforward strategy to construct C–N bonds is playing a pivotal role in synthetic chemistry. Here, we report a photocatalysed protocol to access direct C–H amidation of indoles, enabled by a rationally designed tert-butyl alkyl((perfluoropyridin-4-yl)oxy)carbamate. A series of biologically important aminoindoles were prepared under mild conditions with excellent regioselectivity and broad substrate scope. [ABSTRACT FROM AUTHOR]

An unprecedented electrochemical heterodifunctionalization of α-CF3 alkenes with benzenesulfonyl hydrazides was accomplished in this work, wherein a β-sulfonyl and a α-hydroxyl group were simultaneously incorporated across the olefinic double bond in a single operation. Consequently, a series of potentially medicinally valuable and densely functionalized α-trifluoromethyl-β-sulfonyl tertiary alcohols were assembled under mild conditions. Electrochemically-driven oxidative 1,2-difunctionlization of electron-deficient alkenes well obviates the need for oxidizing reagents, thus rendering this protocol more eco-friendly. [ABSTRACT FROM AUTHOR]

Abstract Background Faba bean (Vicia faba L.) is an important food legume crop, grown for human consumption globally including in China, Turkey, Egypt and Ethiopia. Although genetic gain has been made through conventional selection and breeding efforts, this could be substantially improved through the application of molecular methods. For this, a set of reliable molecular markers representative of the entire genome is required. Results A library with 125,559 putative SSR sequences was constructed and characterized for repeat type and length from a mixed genome of 247 spring and winter sown faba bean genotypes using 454 sequencing. A suit of 28,503 primer pair sequences were designed and 150 were randomly selected for validation. Of these, 94 produced reproducible amplicons that were polymorphic among 32 faba bean genotypes selected from diverse geographical locations. The number of alleles per locus ranged from 2 to 8, the expected heterozygocities ranged from 0.0000 to 1.0000, and the observed heterozygosities ranged from 0.0908 to 0.8410. The validation by UPGMA cluster analysis of 32 genotypes based on Nei's genetic distance, showed high quality and effectiveness of those novel SSR markers developed via next generation sequencing technology. Conclusions Large scale SSR marker development was successfully achieved using next generation sequencing of the V. faba genome. These novel markers are valuable for constructing genetic linkage maps, future QTL mapping, and marker-assisted trait selection in faba bean breeding efforts.

Abstract: A total of 440 lentil (Lens culinaris) accessions, randomly chosen from the National Gene Bank, were employed in the experiment. Fourteen polymorphic SSR markers out of 145 candidate simple sequence repeat (SSR) primer pairs were screened, and 87 allelic variations were detected. Using 14 SSR primer pairs, high level of diversity was detected with average allele number of 6.2143 and Shannon-Weaver index (I) of 1.1869. There was a significant differentiation in the genetic diversity among the 16 diverse geographic groups of the lentil accessions. The genetic diversity within alien accessions was obviously higher than that within Chinese accessions. The 440 accessions were classified into 8 clusters using Structure 2.2 software. Multiplex genetic structure was observed according to the analyses of principal components analysis (PCA), Unweighted Pair Group Method with Arithmetic Mean (UPGMA) cluster, and population structure. The genetic distance within alien population was broader than that within Chinese population. In the Chinese population, accessions from Shanxi, Ningxia, and Gansu showed the highest genetic diversity, and it should be emphasized in genetic resource collection and conservation as well as deeper studies. Furthermore, international exchange of lentil genetic resources should be also enhanced. [Copyright &y& Elsevier]

Herein, a dual photoredox/nickel catalyzed formylation of aryl bromide with commercially available 2,2-dimethoxy- N , N -dimethylethan-1-amine as an effective CO source has been successfully achieved, delivering a series of aromatic aldehydes in moderate to good yields. Compared with the traditional reductive carbonylation process, this newly designed synthetic protocol provides a straightforward toolbox to access aromatic aldehydes, obviating the use of carbon monoxide and stoichiometric reductants. Finally, the utility of this direct formylation reaction was demonstrated in the pharmaceutical analogue synthesis.

Photoinduced generation of phosphoranyl radicals offers a versatile strategy to access a variety of synthetically valuable radicals. A long-standing challenge remains in the regulation of phosphoranyl radical to undergo α-scission pathway, although the β-scission mode has been intensively studied. We herein developed an unprecedented protocol for selective α-scission of the P(OH)R 3 radical intermediate under photocatalytic conditions. This efficient P-C bond cleavage via α-scission of the P(OH)R 3 radicals has been successfully utilized in the alkylation/fluoroalkylation of alkenes.

Reported herein is the design and development of a new photo-induced amidation protocol with the readily available N -chlorosulfonyl carbamate as an effective amidyl-radical precursor, which could be readily prepared from commercial low-cost chlorosulfonyl isocyanate (CSI) and alcohol feedstocks. The synthetic potency of this developed protocol was well demonstrated by direct amidation of various quinoxalin-2(1 H )-ones. The protocol could be further streamlined by implementing a one-pot/two-step/three-component process of CSI, alcohol, and quinoxalin-2(1 H )-one, with significantly improved reaction efficiency. This methodology offers an intriguing opportunity for rapid expansion of nitrogen-containing molecular complexity, thus inspiring comprehensive exploration of a new reaction mode of CSI reagent.

A Giese reaction of aryl bromides with electron-deficient alkenes was developed, enabled by a dual catalyst system containing Ni II complex and Ir III photocatalyst. This protocol could accommodate a variety of aryl bromides and electron-deficient alkenes, delivering the conjugate adducts in up to 97% yield. The utilization of photoexcited (dtbbpy)Ni II (aryl)Br intermediate as an aryl radical source allows this novel transformation of aryl halides, thus expanding the chemical space of excited nickel catalysis.

A visible-light-induced defluorinative dichloromethylation of α-CF 3 alkenes was developed with cheap and readily accessible chloroform simultaneously as a dichloromethylation reagent and reaction medium, leading to the facile preparation of new polyhalogenated scaffolds. Notably, the change from CHCl 3 to CDCl 3 offers a straightforward pathway for accessing the deuterated analogues with excellent degrees of D incorporation. Mechanistic studies suggested the reaction underwent a radical addition of the dichloromethyl radical with alkenes, followed by sequential single-electron transfer and defluorination. This protocol features mild conditions, easy operation, facile scalability, and high efficiency, allowing convenient access to dichloronated gem -difluoroalkenes.

An unprecedented photoredox-catalyzed phosphine-mediated deoxygenation of hexafluoroacetone hydrate was established to accomplish the hydroxylpolyfluoroalkylation of electron-deficient alkenes. A range of bis(trifluoromethyl)carbinols were facilely accessed by using readily available hexafluoroacetone hydrate, instead of toxic gaseous hexafluoroacetone. A range of electron-deficient alkenes are tolerated, giving the corresponding hydro-hydroxylpolyfluoroalkylated products in moderate to high yields. Remarkable features of this synthetic strategy include operational simplicity, mild reaction conditions, excellent regioselectivity, and broad functional group tolerance. The success of this strategy relies on the delicate utilization of aldehyde/ketone-gem-diol intrinsic equilibrium, which offers an innovated open-shell pathway for the assembly of synthetically challenging polyfluoroalkylated scaffolds., (© 2022 Wiley-VCH GmbH.)

A visible light-promoted radical relay of N -allylbromodifluoroacetamide with quinoxalin-2(1 H )-ones was developed in which 5- exo - trig cyclization and C-C bond formation were involved. This protocol was performed under mild conditions to facilely offer a variety of hybrid molecules bearing both quinoxalin-2(1 H )-one and 3,3-difluoro-γ-lactam motifs. These prepared novel skeletons would expand the accessible chemical space for structurally complex heterocycles with potential biological activities.

An unprecedented electrochemical heterodifunctionalization of α-CF 3 alkenes with benzenesulfonyl hydrazides was accomplished in this work, wherein a β-sulfonyl and a α-hydroxyl group were simultaneously incorporated across the olefinic double bond in a single operation. Consequently, a series of potentially medicinally valuable and densely functionalized α-trifluoromethyl-β-sulfonyl tertiary alcohols were assembled under mild conditions. Electrochemically-driven oxidative 1,2-difunctionlization of electron-deficient alkenes well obviates the need for oxidizing reagents, thus rendering this protocol more eco-friendly.

We herein report an unprecedented photoinduced cyclization/defluorination domino process of N -allylbromodifluoroacetamide with cyclic secondary amines. Consequently, a wide array of valuable 3-fluoro-1,5-dihydro-2 H -pyrrol-2-ones were facilely prepared from readily available starting materials under mild conditions. Preliminary mechanistic investigations suggest that a radical chain propagation and amine-promoted defluorination pathway are presumably involved in this transformation.

Abnormalities and variations of the biliary ducts are not rare. Most aberrant bile ducts eventually drain into the descending part of duodenum through the papilla of vater. However, drainage of the left hepatic bile duct into the stomach is extremely rare. A 29-year old man was admitted to the hospital with the diagnosis of biliary reflux gastritis. Comprehensive imaging modalities were performed including electronic endoscopy, endoscopic ultrasonography, endoscopic retrograde cholangiopancreatography and magnetic resonance cholangio-pancreatography. Finally, congenital ectopic left intrahepatic bile duct draining into the stomach was found, which caused biliary reflux gastritis. The patient did not receive any surgery. Good recovery was achieved by medical treatment.