The preparation, structure, and chemistry of hypervalent iodine compounds are reviewed with emphasis on their synthetic application. Compounds of iodine possess reactivity similar to that of transition metals, but have the advantage of environmental sustainability and efficient utilization of natural resources. These compounds are widely used in organic synthesis as selective oxidants and environmentally friendly reagents. Synthetic uses of hypervalent iodine reagents in halogenation reactions, various oxidations, rearrangements, aminations, C–C bond-forming reactions, and transition metal-catalyzed reactions are summarized and discussed. Recent discovery of hypervalent catalytic systems and recyclable reagents, and the development of new enantioselective reactions using chiral hypervalent iodine compounds represent a particularly important achievement in the field of hypervalent iodine chemistry. One of the goals of this Review is to attract the attention of the scientific community as to the benefits of...

Advances in Synthetic Applications of Hypervalent Iodine Compounds

10. Patented Literature 2616 10.1. Esterification 2616 10.2. Ether Formation 2619 10.2.1. Etherification without Cyclization 2619 10.2.2. Etherification with Cyclization 2624 10.3. N-Alkylation 2625 10.4. Other Reactions 2627 11. Summary and Outlook 2628 12. Note Added in Proof 2628 13. Abbreviations Used in This Review 2629 14. Acknowledgments 2629 15. Supporting Information Available 2630 16. References 2630

Mitsunobu and Related Reactions: Advances and Applications

Research and industrial interest in radical C–H activation/radical cross-coupling chemistry has continuously grown over the past few decades. These reactions offer fascinating and unconventional approaches toward connecting molecular fragments with high atom- and step-economy that are often complementary to traditional methods. Success in this area of research was made possible through the development of photocatalysis and first-row transition metal catalysis along with the use of peroxides as radical initiators. This Review provides a brief and concise overview of the current status and latest methodologies using radicals or radical cations as key intermediates produced via radical C–H activation. This Review includes radical addition, radical cascade cyclization, radical/radical cross-coupling, coupling of radicals with M–R groups, and coupling of radical cations with nucleophiles (Nu).

Recent Advances in Radical C-H Activation/Radical Cross-Coupling.

Carbon trifluoromethylation reactions of hydrocarbon derivatives and heteroarenes.

Nucleophilic phosphine catalysis has proven to be a powerful tool in organic synthesis, which can provide easy access to cyclic, bicyclic or polycyclic carbocycles and heterocycles. Owing to their comparatively strong and readily tunable nucleophilicity, phosphines can be easily tailored to efficient annulation reactions with good control over reaction selectivity. This has resulted in a tremendous increase in their scope and in a concomitant number of reports where phosphine-triggered annulation reactions occur. This tutorial review summarizes the recent achievements in this area.

Phosphine-triggered synthesis of functionalized cyclic compounds

According to our previous research on the antiviral activity of β-carboline and tetrahydro-β-carboline derivatives, series of novel tetrahydro-β-carboline derivatives containing acylhydrazone moiety and different substituents at 1 position were designed, synthesized via Pictet-Spengler reaction, and evaluated for their biological activities. Most of these compounds exhibited excellent antiviral activity both in vitro and in vivo . The in vivo inactivation, curative, and protection activities of part of these compounds were much higher than that of ribavirin (36.5%, 35.2%, and 37.1% at 500 μg/mL) and harmine (40.5%, 38.6% and 42.4% at 500 μg/mL). Especially, the in vivo activities of compounds VI-1 (61.4%, 57.2%, and 68.1%) and compound VI-2 (74.5%, 69.0%, and 68.1%) at 500 μg/mL, which were nearly twofold of that of ribavirin at 500 μg/mL. At the same time, the fungicidal results showed that compound IV-2 exhibited more than 60% fungicidal activities against 5 kinds of phytopathogens. Additionally, compound IV-5 exhibited more than 60% larvicidal activity against C. pipiens pallens at 0.25 mg/kg.

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Synthesis of tetrahydro-β-carboline-3-carbohydrazide derivatives based on Pictet-Spengler reaction and their bioactivities

\n\nAim and Objective: During the investigation of sodium nitrite-catalyzed oxidative coupling reaction\nof aryls, an unprecedented C(sp2)-H and C(sp3)-H coupling of substituted 2-aryl acetonitrile was found.\n\n\n\n \nThe structure of the coupled product was confirmed by 1H and 13C NMR spectroscopy\nand high-resolution mass spectrometry (HRMS), and comparison of its derivatives with known compounds.\nThe effects of methoxy group in the benzene ring on the reaction were evaluated.\n\n\n\n The optimized reaction conditions are summarized as follows: CF3SO3H/substrate = 1.5 equiv.,\nNaNO2/substrate = 0.3 equiv., CH3CN as solvent. 2-(4-Methoxyphenyl)acetonitrile and 2-(3,4,5-\ntrimethoxyphenyl)acetonitrile could also generate C(sp2)-H and C(sp3)-H coupling. The coupling reaction occurred\nas a typical radial mechanism.\n\n\n\n An unprecedented cyano-induced, NaNO2-catalyzed oxidative C(sp3)-H and C(sp2)-H coupling\nwas reported. The reaction proceeded under very mild conditions, using O2 in the air as terminal oxidant. The\nunique oxidative manner might provide more inspiration for the development of intriguing oxidative coupling\nreactions.\n

An Unprecedented Cyano-Induced Sodium Nitrite-Catalyzed C(sp3)-H and C(sp2)-H Coupling Reaction

Despite the ubiquity of alkylboronic acids in organic synthesis, their utility as alkyl radical precursors in visible-light-induced photocatalytic reactions is limited by their high oxidation potentials. In this study, we demonstrated that an inorganophosphorus compound can modulate the oxidation potentials of alkylboronic acids so that they can act as alkyl radical precursors. We propose a mechanism based on the results of fluorescence quenching experiments, electrochemical experiments, 11B and 31P NMR spectroscopy, and other techniques. In addition, we describe a simple and reliable alkylation method that has good functional group tolerance and can be used for direct C–B chlorination, cyanation, vinylation, alkynylation, and allylation, as well as late-stage functionalization of derivatized drug molecules. Notably, alkylboronic acids can be selectively activated in the presence of a boronic pinacol ester.

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Alkylboronic acids as alkylating agents: photoredox-catalyzed alkylation reactions assisted by K3PO4

The present invention relates to β-carboline, dihydro-β-carboline and tetrahydro-β-carboline alkaloid derivatives (I) and a method for preparing same and the use in the aspects of preventing and treating plant viruses, fungicides and insecticides. For the meaning of each group in formula (I) see the description. The β-carboline, dihydro-β-carboline and tetrahydro-β-carboline alkaloid derivatives of the present invention show a particularly ourstanding anti-plant virus activity, and also have fungicidal and insecticidal activities.

ß-CARBOLINE, DIHYDRO-ß-CARBOLINE AND TETRAHYDRO-ß-CARBOLINE ALKALOID DERIVATIVES AND PREPARATION METHODS SAME AND USE IN ASPECTS OF PREVENTING AND TREATING PLANT VIRUSES, FUNGICIDES AND INSECTICIDES

Bu 3 P-CS 2 adduct, generated from tributylphosphine anc carbon disulfide, reacted with dialkyl azodicarboxylates and aromatic aldehydes in one-pot to give 1,3,4-thiadiazolidine-2-thiones.

Yuxiu Liu

Papers

Synthesis of tetrahydro-β-carboline-3-carbohydrazide derivatives based on Pictet-Spengler reaction and their bioactivities

An Unprecedented Cyano-Induced Sodium Nitrite-Catalyzed C(sp3)-H and C(sp2)-H Coupling Reaction

Alkylboronic acids as alkylating agents: photoredox-catalyzed alkylation reactions assisted by K3PO4

ß-CARBOLINE, DIHYDRO-ß-CARBOLINE AND TETRAHYDRO-ß-CARBOLINE ALKALOID DERIVATIVES AND PREPARATION METHODS SAME AND USE IN ASPECTS OF PREVENTING AND TREATING PLANT VIRUSES, FUNGICIDES AND INSECTICIDES

The reaction of Bu3P-CS2 adduct with azo compounds and aromatic aldehydes