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We report herein a reexamination of the reactions between sulfoxonium ylides and acetylenic esters. Continuing our previous study of conjugate additions using α‐carbonyl sulfoxonium ylides, we came across an interesting transformation when dimethyl acetylenedicarboxylate (DMAD) was employed as a Michael acceptor. Trisubstituted electron‐deficient 1,3‐dienes and α‐carbonyl vinyl sulfoxides were obtained for the first time from these sulfur ylides, in a stereoselective manner (exclusively forming the E‐isomer), achieving yields of up to 70 % and 83 %, respectively. Selected dienes were subsequently utilized in the synthesis of novel nitrogen heterocycles. Interestingly, when di‐tert‐butyl acetylenedicarboxylate (DtBAD) or alkyl propiolates were evaluated, the isolated product arose from the classical Michael addition, yielding α‐carbonyl vinyl sulfoxonium ylides in yields of up to 89 %. [ABSTRACT FROM AUTHOR]

A Cu(I)‐catalyzed synthesis of α‐arylated sulfoxonium ylides has been achieved from mesitylene‐derived diaryliodonium salts and α‐carbonyl sulfoxonium ylides. The reaction is believed to proceed via an electrophilic Cu(III)‐aryl intermediate that can be trapped upon nucleophilic attack of the sulfoxonium ylide precursor. The reaction was tolerant to both α‐keto and α‐ester‐derived sulfoxonium ylides, to drug‐derived ylide motifs and to electronically‐diverse arenes, and enabled the direct synthesis of 32 α‐aryl‐sulfoxonium ylides in 42–85% yield. [ABSTRACT FROM AUTHOR]

The present study highlights a novel and advantageous protocol for accessing carbamates through the well‐established three‐component coupling reaction involving CO2, amines, and alkyl halides. By employing an immobilized organic base, operating under mild reaction conditions, an array of alkyl carbamates in yields of up to 95 % could be isolated. This approach offers a broad and versatile product scope, allowing for the facile modification of both the amine and alkyl halide reactants. Notably, the pioneering use of an immobilized organic base, specifically the polymer‐supported 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (PS‐DBU), in this three‐component reaction eliminates the need for classical purification steps, streamlining the process. To ensure practicality and sustainability, extensive studies were conducted to verify the recovery and reusability of the polymer‐supported DBU catalyst, which consistently maintained the high chemical yield of the carbamates across multiple cycles. Overall, this innovative protocol represents a significant advancement in carbamate synthesis, combining efficiency, generality, and the potential for DBU recycling. [ABSTRACT FROM AUTHOR]

Sulfur ylides are an important class of organic compounds due to their ability to perform many different transformations that can give diverse and interesting products with a high degree of complexity. Although metal-catalyzed transformations are frequent in this class of compounds, organocatalyzed transformations remain scarce. From initial works, this review aims to show organocatalyzed transformations from sulfur ylides, involving cyclopropanation and formal N–H, S–H, and C–H insertion reactions, including enantioselective versions. The proposed mechanisms and the modes of activation of these organocatalysts will be covered. Furthermore, advances in this area and potential challenges to be circumvented in the near future will also be discussed. [ABSTRACT FROM AUTHOR]

Sulfoxonium ylides in recent years have proved to be versatile building blocks and have found applications in the synthesis of structurally diverse organic molecules. In this work, we report a new oxidative, molecular iodine‐mediated transformation on sterically encumbered arylated sulfoxonium ylides, which give access to 1,2‐dicarbonyl containing compounds. Twenty‐six examples have been realized (47–92 % yields), with structural diversity modified at two key sites on the sulfoxonium ylide reactants. Furthermore, the protocol benefits from the use of inexpensive molecular iodine to mediate the oxidation and, from a sustainability viewpoint, short reaction times (30 minutes), ambient temperature, and ethyl acetate as a greener reaction solvent. Experimental studies also gave insight to the mechanism of the reaction, involving DMSO as an oxygen source. [ABSTRACT FROM AUTHOR]

Substituted naphthols (SNs) are an important class of chemical compounds present in many natural and synthetic products with biological and pharmaceutical activities. Moreover, the naphthol skeleton has been employed as a starting material for the development of drug molecules and natural products. Thus, different synthetic methods to access naphthol cores have been reported using diverse starting materials and chemical strategies. This review article describes literature on synthetic methodologies of substituted naphthols synthesized from alkynes, sulfur ylides, diazo substrates, alkenes/cyclopropenes, ketones/oxanorbenes/furans, amongst other key reactants. [ABSTRACT FROM AUTHOR]

Solvent-free O-H insertion reactions in the presence of diazo carbonyl compounds were carried-out in very mild conditions. Unlike the traditional metal-catalysed version, employing rhodium acetate dimer, this method uses eco-friendly silica-supported HClO4 as the catalyst. Only 0.3 mol% of this Brønsted acid catalyst, that can also be recycled several times, is necessary to guarantee very good yields (up to 97%) in the O-H insertion reactions. Reaction set-up is simple and permitted the preparation of forty-three α-hydroxyand α-alkoxy esters/ketones in just 1 h and at room temperature. [ABSTRACT FROM AUTHOR]