Physiological and Cellular Ultrastructural Responses of Fort. under Salt Stress.

This study aimed to analyze the effects of salt stress on the growth physiology and plant-cell ultrastructure of Fort. () to evaluate its adaptability under salt stress. The effects of different concentrations of salt (NaCl; 0, 25, and 300 mmol·L) on the agronomic traits, activities of related enzymes, ion balance, and mesophyll-cell ultrastructure of were studied in a controlled pot experiment.

Iron-Catalyzed Sulfonylthiocyanation of α,β-Unsaturated Amides/Esters via the Insertion of Sulfur Dioxide.

An iron-catalyzed four-component sulfonylthiocyanation between α,β-unsaturated amides/esters, TMSNCS, aryldiazonium tetrafluoroborates, and sulfur dioxide (from SOgen) is demonstrated. This protocol is characterized by mild reaction conditions, good functional group compatibility, broad substrate scope, and good to excellent yields, providing a feasible method for the preparation of thiocyanated sulfone compounds. The preliminary mechanism investigation shows that a radical pathway may be involved in the process.

Redox-Neutral Rhodium(III)-Catalyzed Chemospecific and Regiospecific [4+1] Annulation between Indoles and Alkenes for the Synthesis of Functionalized Imidazo[1,5-]indoles.

Exploiting internal alkenes embedded with an oxidizing function/leaving group as a rare and unconventional one-carbon unit, a redox-neutral rhodium(III)-catalyzed chemo- and regiospecific [4+1] annulation between indoles and alkenes for the synthesis of functionalized imidazo[1,5-]indoles has been achieved. Internal alkenes employed here can fulfill an unusual [4+1] annulation rather than normal [4+2] annulation/C-H alkenylation. This method is characterized by excellent chemo- and regioselectivity, broad substrate scope, good functional group tolerance, good to high yields, and redox-neutral conditions.

Additive-Controlled Divergent Synthesis of Tetrasubstituted 1,3-Enynes and Alkynylated 3-Pyrrolo[1,2-]indol-3-ones via Rhodium Catalysis.

Herein, we report the additive-controlled divergent synthesis of tetrasubstituted 1,3-enynes and alkynylated 3-pyrrolo[1,2-]indol-3-ones through rhodium-catalyzed C-H alkenylation/DG migration and [3+2] annulation, respectively. This protocol features rare directing group migration in 1,3-diyne-involved C-H activation, excellent regio- and stereoselectivity, excellent monofunctionalization over difunctionalization, broad substrate scope, moderate to high yields, good functional group compatibility, and mild redox-neutral conditions.

Design and Applications of a SO Surrogate in Palladium-Catalyzed Direct Aminosulfonylation between Aryl Iodides and Amines.

A new SO surrogate is reported that is cheap, bench-stable, and can be accessed in just two steps from bulk chemicals. Essentially complete SO release is achieved in 5 minutes. Eight established sulfonylation reactions proceeded smoothly by ex situ formation of SO by utilizing a two-chamber system in combination with the SO surrogate.

DGT methodology is more sensitive than conventional extraction strategies in assessing amendment-induced soil cadmium availability to rice.

Using diffusive gradients in thin films (DGT) is a recently developed alternative method of rapidly evaluating the bioavailability of metals in soil. However, the method has found only limited application in systematic assessment of the bioavailability of cadmium (Cd) in red limestone paddy soils treated with different soil amendments. Of the four methods compared for estimating Cd content of rice grains from plants grown in such soils of central China treated with eleven different soil amendments in pot culture, Cd content of DGT-labile soil was significantly correlated to Cd concentrations in brown rice (R = 0.

Rhodium(III)-Catalyzed C-H Alkenylation/Directing Group Migration for the Regio- and Stereoselective Synthesis of Tetrasubstituted Alkenes.

An efficient Rh(III)-catalyzed C-H alkenylation/directing group migration cascade between indoles and alkynes for the assembly of tetrasubstituted alkenes is reported. The carbamoyl directing group migrates to the carbon of the alkene moiety of the products through rare Rh-catalyzed C-N bond cleavage after the C-H alkenylation step and thus acts as an internal amidation reagent. This protocol shows broad substrate scope, excellent regio/stereoselectivity, and good to excellent yields.

Nickel-Catalyzed Intramolecular Desulfitative C-N Coupling: A Synthesis of Aromatic Amines.

A nickel-catalyzed intramolecular C-N coupling reaction via SO extrusion is presented. The use of a catalytic amount of BPh allows the transformation to take place under much milder conditions (60 °C) than previously reported C-N coupling reactions by CO or CO extrusion (160-180 °C). In addition, this method displays good functional group tolerance and versatility, as it can be applied to the synthesis of dialkyl aryl amines, alkyl diaryl amines, and triaryl amines.

Green and Facile Assembly of Diverse Fused -Heterocycles Using Gold-Catalyzed Cascade Reactions in Water.

The present study describes an AuPPh₃Cl/AgSbF₆-catalyzed cascade reaction between amine nucleophiles and alkynoic acids in water. This process proceeds in high step economy with water as the sole coproduct, and leads to the generation of two rings, together with the formation of three new bonds in a single operation. This green cascade process exhibits valuable features such as low catalyst loading, good to excellent yields, high efficiency in bond formation, excellent selectivity, great tolerance of functional groups, and extraordinarily broad substrate scope.

Recent Advances in the Addition of Amide/Sulfonamide Bonds to Alkynes.

The addition of amide/sulfonamide bonds to alkynes is not only one of the most important strategies for the direct functionalization of carbon⁻carbon triple bonds, but also a powerful tool for the downstream transformations of amides/sulfonamides. The present review provides a comprehensive summary of amide/sulfonamide bond addition to alkynes, including direct and metal-free aminoacylation, based-promoted aminoacylation, transition-metal-catalyzed aminoacylation, organocatalytic aminoacylation and transition-metal-catalyzed aminosulfonylation of alkynes up to December 2018. The reaction conditions, regio- and stereoselectivities, and mechanisms are discussed and summarized in detail.

FeCl₃∙6H₂O/TMSBr-Catalyzed Rapid Synthesis of Dihydropyrimidinones and Dihydropyrimidinethiones under Microwave Irradiation.

An efficient and practical protocol has been developed to synthesize dihydropyrimidinones and dihydropyrimidinethiones through FeCl₃∙6H₂O/TMSBr-catalyzed three-component cyclocondensation under microwave irradiation. This approach features high yields, broad substrate scope, short reaction time, mild reaction conditions, operational simplicity and easy work-up, thus affording a versatile method for the synthesis of dihydropyrimidinones and dihydropyrimidinethiones.