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Abstract The direct C−H acyloxylation of polycyclic aromatic hydrocarbons (PAHs) with carboxylic acids as the acyloxylating agents was achieved via the electron‐donor‐acceptor (EDA) complexes between PAHs andN‐iodosuccinimide (NIS). This visible light‐assisted metal‐free C−H acyloxylation reaction provides an easy access to the desired aryl carboxylates from readily available PAHs and aliphatic and aromatic carboxylic acids under mild reaction conditions. magnified image 

Abstract The direct synthesis of α‐sulfonyl ketones was accomplished by a multicomponent reaction of styrene derivatives, anilines,t‐butyl nitrite, 1,4‐diazabicyclo[2.2.2]octane‐sulfur dioxide (DABSO), and oxygen catalyzed by salicylic acid. The aryl radicals generated from aniline derivatives andt‐butyl nitrite under the catalysis of salicylic acid was sulfonylated by DABSO to generate the arylsulfonyl radicals, which reacted further with styrenes, and then oxidized by oxygen to give the title compounds. Under the optimized conditions, the title compounds were obtained in good yields at ambient temperature within 1.5–2 h. 

Abstract Natural products are the great sources of drugs and leading compounds in drug discovery, as it has been estimated that most of the current medicines are derived from natural products. Total synthesis of natural products, especially those of biological activities, has been an important part of organic chemistry, which, besides its potential practical utilities, also provides new inspirations and novel synthetic methodologies. Over the past two decades, organocatalysis has been shown to be very effective in controlling the stereochemistry of the reaction products and has found many applications in the asymmetric synthesis of natural products and related compounds. In this review we will attempt to summarize some applications of asymmetric organocatalysis in the total synthesis of natural products and related compounds in the past seven years. 

Abstract The diastereodivergent synthesis of bridged 1,2,3,4‐tetrahydroisoquinoline derivatives has been achieved by using appropriate modularly designed organocatalysts (MDOs) that are self‐assembled in situ from amino acids and cinchona alkaloid derivatives. The domino Mannich/aza‐Michael/aldol reaction between (E)‐2‐[2‐(3‐aryl‐3‐oxoprop‐1‐en‐1‐yl)phenyl]acetaldehydes and ethyl or benzyl (E)‐2‐[(4‐methoxyphenyl)imino]acetates catalyzed by MDOs gives two different diastereomers of the desired bridged tetrahydroisoquinolines in good yields and excellent diastereoselectivities (up to 99:1 dr) and enantioselectivities (up to >99%ee). The diastereodivergence was achieved in the aldol reaction step. magnified image 

A highly enantio- and diastereoselective method for the synthesis of functionalized chroman-2-ones and chromanes was achieved by using an organocatalytic domino Michael/hemiacetalization reaction of aliphatic aldehydes and ( E )-2-(2-nitrovinyl)phenols followed by a PCC oxidation and dehydroxylation, respectively. Using the modularly designed organocatalysts (MDOs) self-assembled from cinchona alkaloid derivatives and amino acids in the reaction media, the title products were obtained in good to high yields (up to 97%) and excellent diastereoselectivities (up to 99 : 1 dr) and enantioselectivities (up to 99% ee). 

Abstract Sustainability in chemical synthesis is a major aspect of the current synthetic endeavors and, therefore, mimicking the biological process in the laboratory nowadays has the highest priority. Towards achieving this goal, designing organic reactions in domino mode rather than the multistep synthetic pathways and using organocatalysis instead of metal catalysis have received a lot of attention due to the inherent advantages of these processes in terms of synthetic efficiency and sustainability. As a result, the field of asymmetric organocatalytic domino reactions has witnessed tremendous progress in recent years. This review attempts to summarize the latest developments in asymmetric organocatalyzed domino reactions since 2012, with the emphasis on the catalysts and reaction modes. Discussions on the reaction mechanisms and the applications of the developed domino reaction methods in the synthesis of biologically active molecules and natural products are also included when appropriate. magnified image 

The ring-opening of cyclic ethers (epoxide, oxetane, THF, and THP) by carboxylic acids was achieved by using N-iodosuccinimide (NIS) or N-bromosuccinimide (NBS) and triphenylphosphine under the irradiation of blue light. The corresponding omega-haloalkyl carboxylates were obtained under mild reaction conditions. The reaction is believed to work through a halogen bond complex between NIS (or NBS) and triphenylphosphine, which, upon irradiation with blue light, produces the key phosphine radical cation intermediate that initiates the ring-opening reactions. 

A direct one-pot alkylation-aminoxidation of styrene derivatives was achieved by using in-situ-generated alkyl and N-oxyl radicals. The corresponding O-alkylated hydroxylamine derivatives were obtained in moderate to good yields. The reaction features the generation of the alkyl radicals from phenyliodine(III) dicarboxylates via an organocatalytic process, the use of phenyliodine(III) dicarboxylates as the source of the alkyl radicals and the oxidant for the generation of the N-oxyl radicals, and the first generation of the β-enaminyl radicals via a HAT process and their use as the single-electron donors. 

The α-acyloxylcarbonyl motif can be found in many important pharmaceuticals and biologically active natural products and their derivatives. In this manuscript, the direct synthesis of α-acyloxylketones from ketones and readily available carboxylic acids was realized using a photo-assisted halogen bond-mediated organocatalytic α-acyloxylation reaction. The desired α-acyloxylation products were obtained in good to high yields.