An I(I)/I(III) Catalysis Route to the Heptafluoroisopropyl Group: A Privileged Module in Contemporary Agrochemistry

Synthesis ◽  
2021 ◽  
Author(s):  
Victor Martín-Heras ◽  
Constantin G. Daniliuc ◽  
Ryan Gilmour
Keyword(s):  
Functional Groups ◽  
Hypervalent Iodine ◽  
Aryl Ring ◽  
Iodine Species ◽  
Single Operation ◽  
Group A ◽  
Molecule Design ◽  
In Situ Generation

The heptafluoroisopropyl group is emerging as a privileged chemotype in contemporary agrochemistry and features prominently in the current portfolio of leading insecticides. To reconcile the expansive potential of this module with the synthetic challenges associated with preparing crowded, fluorinated motifs, I(I)/I(III) catalysis has been leveraged. Predicated on in situ generation of p-TolIF2, this route enables the direct difluorination of α-trifluoromethyl-β-difluoro-styrenes in a single operation. This formal addition of fluorine across the alkene π-bond is efficient (up to 91%) and is compatible with a broad range of functional groups. The ArCF(CF3)2 moiety is conformationally pre-organized, with the C(sp3)-F bond co-planar to the framework of the aryl ring, thereby minimizing 1,3-allylic strain. Moreover, orthogonal multipolar C-F•••C=O interactions have been identified in a phathalimide derivative. It is envisaged that this programmed vicinal difluorination enabled by a hypervalent iodine species will find application in functional molecule design in a broader sense.

Hypervalent iodine catalysis for selective oxidation of Baylis–Hillman adducts via in situ generation of o-iodoxybenzoic acid (IBX) from 2-iodosobenzoic acid (IBA) in the presence of oxone

2016 ◽  
Vol 40 (12) ◽  
pp. 10300-10304 ◽  
Author(s):  
Raktani Bikshapathi ◽  
Parvathaneni Sai Prathima ◽  
Vaidya Jayathirtha Rao
Keyword(s):  
Selective Oxidation ◽  
Carbonyl Compounds ◽  
Hypervalent Iodine ◽  
In Situ Generation ◽  
Iodosobenzoic Acid ◽  
High Yields

An efficient, eco-friendly protocol for selective oxidation of primary and secondary Baylis–Hillman alcohols to the corresponding carbonyl compounds in high yields has been developed with 2-iodosobenzoic acid (IBA).

The aryl iodine-catalyzed organic transformation via hypervalent iodine species generated in situ

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Xuemin Li ◽  
Guangchen Li ◽  
Yifu Cheng ◽  
Yunfei Du
Keyword(s):  
Organic Synthesis ◽  
Oxidative Coupling ◽  
Hypervalent Iodine ◽  
Organic Transformations ◽  
Aryl Iodide ◽  
Oxidative Reaction ◽  
Iodine Species ◽  
Iodine Chemistry

Abstract The application of hypervalent iodine species generated in situ in organic transformations has emerged as a useful and powerful tool in organic synthesis, allowing for the construction of a series of bond formats via oxidative coupling. Among these transformations, the catalytic aryl iodide can be oxidized to hypervalent iodine species, which then undergoes oxidative reaction with the substrates and the aryl iodine regenerated again once the first cyclic cycle of the reaction is completed. This review aims to systematically summarize and discuss the main progress in the application of in situ-generated hypervalent iodine species, providing references and highlights for synthetic chemists who might be interested in this field of hypervalent iodine chemistry.

Synthesis of Oxazoline and Oxazole Derivatives by Hypervalent-Iodine-Mediated Oxidative Cycloaddition Reactions

Synthesis ◽  
2020 ◽  
Vol 52 (16) ◽  
pp. 2299-2310 ◽  
Author(s):  
Akira Yoshimura ◽  
Akio Saito ◽  
Viktor V. Zhdankin ◽  
Mekhman S. Yusubov
Keyword(s):  
Heterocyclic Compounds ◽  
Short Review ◽  
Active Species ◽  
Hypervalent Iodine ◽  
Cycloaddition Reactions ◽  
Iodine Species ◽  
Oxazole Derivatives

Organohypervalent iodine reagents are widely used for the preparation of various oxazolines, oxazoles, isoxazolines, and isoxazoles. In the formation of these heterocyclic compounds, hypervalent iodine species can serve as the activating reagents for various substrates, as well as the heteroatom donor reagents. In recent research, both chemical and electrochemical approaches toward generation of hypervalent iodine species have been utilized. The in situ generated active species can react with appropriate substrates to give the corresponding heterocyclic products. In this short review, we summarize the hypervalent-iodine­-mediated preparation of oxazolines, oxazoles, isoxazolines, and isoxazoles starting from various substrates.1 Introduction2 Synthesis of Oxazolines3 Synthesis of Oxazoles4 Synthesis of Isoxazolines5 Synthesis of Isoxazoles6 Conclusion

scholarly journals Selective benzylic C–H monooxygenation mediated by iodine oxides

2019 ◽  
Vol 15 ◽  
pp. 602-609
Author(s):  
Kelsey B LaMartina ◽  
Haley K Kuck ◽  
Linda S Oglesbee ◽  
Asma Al-Odaini ◽  
Nicholas C Boaz
Keyword(s):  
Selective Oxidation ◽  
High Yield ◽  
Hypervalent Iodine ◽  
Iodine Species ◽  
Mechanistic Analysis ◽  
Substrate Tolerance ◽  
Iodine Oxides ◽  
Moderate Yield

A method for the selective monooxdiation of secondary benzylic C–H bonds is described using an N-oxyl catalyst and a hypervalent iodine species as a terminal oxidant. Combinations of ammonium iodate and catalytic N-hydroxyphthalimide (NHPI) were shown to be effective in the selective oxidation of n-butylbenzene directly to 1-phenylbutyl acetate in high yield (86%). This method shows moderate substrate tolerance in the oxygenation of substrates containing secondary benzylic C–H bonds, yielding the corresponding benzylic acetates in good to moderate yield. Tertiary benzylic C–H bonds were shown to be unreactive under similar conditions, despite the weaker C–H bond. A preliminary mechanistic analysis suggests that this NHPI-iodate system is functioning by a radical-based mechanism where iodine generated in situ captures formed benzylic radicals. The benzylic iodide intermediate then solvolyzes to yield the product ester.

Hofmann Rearrangement of Carboxamides Mediated by Hypervalent Iodine Species Generated in Situ from Iodobenzene and Oxone: Reaction Scope and Limitations

2010 ◽  
Vol 12 (20) ◽  
pp. 4644-4647 ◽  
Author(s):  
Aleksandra A. Zagulyaeva ◽  
Christopher T. Banek ◽  
Mekhman S. Yusubov ◽  
Viktor V. Zhdankin
Keyword(s):  
Hypervalent Iodine ◽  
Hofmann Rearrangement ◽  
Iodine Species

New synthesis of spirocycles by utilizing in situ forming hypervalent iodine species

2011 ◽  
Vol 9 (20) ◽  
pp. 6899 ◽  
Author(s):  
Toshifumi Dohi ◽  
Tomofumi Nakae ◽  
Yohei Ishikado ◽  
Daishi Kato ◽  
Yasuyuki Kita
Keyword(s):  
Hypervalent Iodine ◽  
Iodine Species ◽  
In Situ Forming ◽  
New Synthesis

Hypervalent Iodine-mediated/Catalyzed Oxidative Cycloisomerization/Annulation of Alkynes for Metal-free Synthesis of Oxazoles

2020 ◽  
Vol 24 (18) ◽  
pp. 2048-2069
Author(s):  
Akio Saito
Keyword(s):  
Functional Groups ◽  
Single Step ◽  
Biologically Active ◽  
Hypervalent Iodine ◽  
Sustainable Chemistry ◽  
Metal Free ◽  
Triple Bonds ◽  
Iodine Species ◽  
Low Toxicity ◽  
Synthetic Intermediates

Since oxazoles have found widespread applications not only as synthetic intermediates but also as biologically active compounds, much effort has been focused on developing novel and efficient methods for the synthesis of this heterocycle. From the viewpoint of green and sustainable chemistry, hypervalent iodine and other halogen reagents have gained increasing popularity in metal-free oxidative transformation due to their low toxicity, transition-metal-like reactivity, high stability, easy handling and other benefits. In this account, our two approaches to the metal-free synthesis of oxazoles by means of a peculiar activation of alkynes by iodine species are described with the related contexts. One is iodine(III)-mediated/catalyzed oxidative cycloisomerization reactions of N-propargyl amides for the preparation of oxazoles bearing various functional groups at their side chains. In these reactions, iodine(III) species works as a donor of various heteroatomic functional groups as well as an activator of carbon-carbon triple bonds in a single step. Furthermore, this methodology can be extended to iodine(III)-mediated/catalyzed oxidative annulation of alkynes and nitriles as another approach, in which heteroatoms on iodine(III) species are incorporated in the azole rings.

Rapid in Situ Generation of Benzene Diazonium Ions under Basic Aqueous Conditions from Bench-Stable Triazabutadienes

Synlett ◽  
2017 ◽  
Vol 28 (14) ◽  
pp. 1767-1770
Author(s):  
Jie He ◽  
Flora Kimani ◽  
John Jewett
Keyword(s):  
Functional Groups ◽  
Large Degree ◽  
Π Interactions ◽  
Diazonium Ions ◽  
Degree Of Stability ◽  
Acidic Conditions ◽  
In Situ Generation ◽  
Aqueous Conditions ◽  
Benzene Diazonium

Aryl diazonium ions are useful across a range of chemical/biochemical areas. These species are generally made using strongly acidic conditions, which can be detrimental to acid-sensitive functional groups. The ability to generate benzene diazonium ions under basic aqueous conditions is reported herein along with newfound understanding on the aqueous reactivity of solubilized triazabutadienes whereby π-interactions appear to confer a large degree of stability.

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