HFIP in Organic Synthesis

Chemical Reviews, Journal Year: 2022, Volume and Issue: 122(15), P. 12544 - 12747

Published: July 17, 2022

1,1,1,3,3,3-Hexafluoroisopropanol (HFIP) is a polar, strongly hydrogen bond-donating solvent that has found numerous uses in organic synthesis due to its ability stabilize ionic species, transfer protons, and engage range of other intermolecular interactions. The use this exponentially increased the past decade become choice some areas, such as C–H functionalization chemistry. In review, following brief history HFIP an overview physical properties, literature examples reactions using or additive are presented, emphasizing effect each reaction.

Language: Английский

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Diastereoselective [3 + 1] Cyclization Reaction of Oxindolyl Azaoxyallyl Cations with Sulfur Ylides: Assembly of 3,3′-Spiro[β-lactam]-oxindoles

Organic Letters, Journal Year: 2021, Volume and Issue: 23(4), P. 1451 - 1456

Published: Feb. 1, 2021

Oxindoles and β-lactams are attractive structural motifs because of their unique biological importance. However, the fusion two moieties featuring 3,3′-spirocyclic scaffolds is a challenging task in organic synthesis. Herein we designed novel type oxindole-based azaoxyallyl cation synthons, which could readily participate [3 + 1] cyclization with sulfur ylides. With this protocol, collection 3,3-spiro[β-lactam]-oxindoles were facilely produced up to 94% yield perfect diastereoselectivity.

Language: Английский

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Organocatalytic Enantioselective [4+3]‐Cycloadditions of Azaoxyallyl Cations with 2‐Aminophenyl Enones

Advanced Synthesis & Catalysis, Journal Year: 2021, Volume and Issue: 363(17), P. 4197 - 4203

Published: July 12, 2021

Abstract The first organocatalytic asymmetric [4+3]‐cycloaddition of 2‐aminophenyl α,β‐unsaturated carbonyls with in situ generated azaoxyallyl cations was developed, and enantioenriched functionalized seven‐membered 1,4‐benzodiazepine‐3‐ones were obtained good yields excellent enantioselectivities. This approach also extended to the δ‐hydroxy carbonyls, affording 1,4‐oxazepanes one step under mild conditions. Several novel adducts demonstrated promising bioactivity prevention peripheral nerve degeneration. magnified image

Language: Английский

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α‐Halocarbonyls as a Valuable Functionalized Tertiary Alkyl Source

ChemistryOpen, Journal Year: 2024, Volume and Issue: unknown

Published: July 11, 2024

Abstract This review introduces the synthetic organic chemical value of α‐bromocarbonyl compounds with tertiary carbons. compound a carbon has been used primarily only as radical initiator in atom transfer polymerization (ATRP) reactions. However, recent development photo‐radical reactions (around 2010), research on use alkyl precursors became popular 2012). As more examples were reported, studied not radicals but also for their applications organometallic and ionic That is, act nucleophiles well electrophiles. The carbonyl group is attractive because it allows skeleton to be converted after reaction, being applied total synthesis. In our survey until 2022, can perform full range necessary synthesis, including multi‐component reactions, cross‐coupling, substitution, cyclization, rearrangement, stereospecific asymmetric α‐Bromocarbonyl have created new trend alkylation, which then had limited reaction patterns focuses how chemistry.

Language: Английский

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Transition-metal-free synthesis of 1,4-benzoxazepines via [4+3]-cycloaddition of para-quinone methides with azaoxyallyl cations

Science China Chemistry, Journal Year: 2020, Volume and Issue: 64(1), P. 61 - 65

Published: Aug. 21, 2020

Language: Английский

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Synthesis of Benzotriazepin-1-ones via Decarboxylative [4 + 3]-Annulation of Isatoic Anhydrides with Nitrile Imines

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(11), P. 7290 - 7301

Published: May 17, 2023

A novel and streamlined approach to synthesizing benzotriazepin-1-ones has been developed through a hexafluoroisopropanol-promoted decarboxylative cascade reaction between isatoic anhydrides hydrazonoyl chloride. The [4 + 3] annulation of hexafluoroisopropyl 2-aminobenzoates with nitrile imines, generated in situ, is key feature this innovative reaction. This offered simple efficient method for broad range structurally intricate highly functional benzotriazepinones.

Language: Английский

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Aza‐oxyallyl Cations and Their Applications in (3+m) Cycloaddition Reactions

European Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 2022(47)

Published: Oct. 10, 2022

Abstract Aza‐oxyallyl cations, as proposed by Sheehan in the 1960s have garnered significant attention among synthetic organic community, owing to their diverse reactivity profile for constructing N‐scaffolds of biological interest. During its initial growth, aza‐oxyallyl cations were used effectively a 3‐unit synthon 1,3 dipoles create N‐heterocycles via cycloaddition reactions, wherein cation served electrophilic counterpart. Recently, new variations been reported, including usage 1,4 dipole domino and unique alkylating ability heteroatoms. This review article provides an update recent developments this area prevailing mechanistic insight.

Language: Английский

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Diastereoselective (3+3) Cycloaddition of Azomethine Imines with In Situ Formed Azaoxyallyl Cations from α‐Halohydroxamate

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(10), P. 1607 - 1612

Published: May 6, 2023

Abstract A diastereoselective (3+3) cycloaddition of azomethine imines and in situ‐ generated azaoxyallyl cations from α ‐halohydroxamate promoted by a Brønsted base has been developed. series pyrazolo [1,2‐a][1,2,4]triazin‐6‐ones were accessed with up to 95% yields diastereoselectivities greater than 20:1. The asymmetric version this reaction was explored moderate enantioselectivity achieved after screening cinchonine‐derived chiral catalysts. magnified image

Language: Английский

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A Facile Approach to Benzosultam‐fused 4‐Imidazolidinone Derivatives from N‐Sulfonyl Ketimine and α‐Halogenated Hydroxamates

ChemistrySelect, Journal Year: 2022, Volume and Issue: 7(4)

Published: Jan. 24, 2022

Abstract The novel benzosultam‐fused 4‐imidazolidinone scaffold was constructed by a concise [3+2] annulation reaction of α‐halogenated hydroxamates and N‐sulfonyl ketimine for the first time. transformation proceeded smoothly under mild transition‐metal‐free conditions in moderate to excellent yields (up 95 %). Moreover products are potentially useful promising medicinal research.

Language: Английский

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Metal-free synthesis of 1,4-benzodiazepines and quinazolinones from hexafluoroisopropyl 2-aminobenzoates at room temperature

RSC Advances, Journal Year: 2021, Volume and Issue: 11(9), P. 4966 - 4970

Published: Jan. 1, 2021

Herein, we describe the novel reactivity of hexafluoroisopropyl 2-aminobenzoates. The metal-free synthesis 1,4-benzodiazepines and quinazolinones from 2-aminobenzoates has been developed at room temperature. These procedures feature good functional group tolerance, mild reaction conditions, excellent yields. newly formed products can readily be converted to other useful N-heterocycles. Moreover, their derivatives showed potent anticancer activities in vitro by MTT assay.

Language: Английский

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